Create an Account  |   Log In

View All »Matching Part Numbers


Your Shopping Cart is Empty
         

Screw Thread Adapters


  • Imperial, Metric, and Imperial-Metric Adapters
  • M3, M4, M6, 4-40, 6-32, 8-32, and 1/4"-20 Thread Adapters
  • Useful for Mounts, Posts, and Post Holders
  • Two Types of Counterbore Adapters

AI25E8E

Internal 8-32

Internal 1/4"-20

AS4M8E

Internal M4 x 0.7

External 8-32

CBA25E

1/4"-20 Thread

0.40" Outer Diameter

AE8E25E

Internal 8-32

External 1/4"-20

AP6M8E

External M6 x 1.0

External 8-32

MSA8

Internal 4-40

External 8-32

MSA25

Internal 4-40

External 1/4"-20

HW-KIT6

Thread Adapter Kit

Related Items


Please Wait

Rail Carrier Cross Section with SD1 Counterbore Adapter Ring

Threading Adapters

  • Machined from 303 Stainless Steel
  • Adapt One Common Thread Standard to Another
  • Ideal for Mounting Posts

Thorlabs' selection of thread adapters offers numerous options for switching between M3, M4, M6, 4-40, 6-32, 8-32, and 1/4"-20 thread sizes. Choose from external-to-internal, external-to-external, or internal-to-internal thread adapters. We also offer internal-to-external threaded stud adapters. Our external-to-external and internal-to-external thread adapters can be adjusted with a screwdriver on either end. The internal-to-internal thread adapters and internal-to-external threaded stud adapters feature a through hole to provide additional torque when tightening or loosening.

The Mini-Series thread adapters can be used to make the Mini-Series posts compatible with our extensive range of optical mounts.

Counterbore Adapters

Threaded counterbore adapters are used to convert a counterbore to a threaded hole. A part such as the KM100 kinematic mirror mount features counterbores to provide imperial and metric compatibility. A cap screw is typically used to fasten these mounts to a post, but in some instances it is necessary to attach the mount to a post with a fixed threaded stud. The counterbore adapter allows parts, such as the KM100, to be post mounted when a cap screw cannot be used.

The SD1 is an adapter ring that provides a means to attach 8-32 (M4) tapped components to 1/4"-20 (M6) counterbored parts. One possible use for the SD1 is in a dovetail optical rail setup where the RC1 rail carriers feature a 1/4" (M6) counterbore. Optic mounts are commonly attached to RC1 rail carriers and usually require the SD1 adapter as most optic mounts are 8-32 (M6) tapped.

Thread Adapter Kits

Thread Adapter Kits are available in both imperial and metric varieties. Both kits come packaged in an organizing box with convenient scaled drawing labels and contain our most popular thread adapters. See below for a list of the specific adapters contained in each kit.


Posted Comments:
tjschongar  (posted 2018-07-29 12:36:50.47)
MSA8 MINI What thread pitch is the 8-32side? unc of unf i need to get the right tap size
YLohia  (posted 2018-07-30 09:43:00.0)
The thread count is 32 threads in an inch, which translates to 0.79375 mm pitch. The 8-32 thread is UNC.
keweima  (posted 2015-03-10 16:47:33.74)
Do you carry anything like this but for a M2.5 thread instead of M3?
cdaly  (posted 2015-03-25 02:12:57.0)
Response from Chris at Thorlabs: We did at one time offer M2.5 adapters to 1/4-20 threads as a standard part, AE25M25E, but this has since been obsoleted. I will look into the possibility of offering it as a custom and contact you directly.
iain  (posted 2014-09-04 12:55:30.963)
Do you make an adapter with external M4 and external 1/4"-20 threads? This would be useful for screwing the M4 end of a 12.7 mm Ø post into an imperial optical table.
cdaly  (posted 2014-09-04 10:02:05.0)
Response from Chris at Thorlabs: There's no external to external adapter, but we do have an internal to external one that should work for you. AE4M25E would thread over the M4 stud which comes with the metric 1/2" series posts and leave you with external 1/4-20 threads, allowing you to mount the M4 side flush with an imperial the table.
Adam  (posted 2010-05-17 15:18:58.0)
A response from Adam at Thorlabs to makarov: Thank you very much for the customer inspired new product idea. I agree that this would be a great addition to the catalog and fill and important void in our thread adapters. I am currently working on a quotation for these custom thread adapters and will confirm the dimensions of the custom product via email.
makarov  (posted 2010-05-16 01:43:11.0)
I would like to buy AP4M4E adapter, external M4 to external #4-40 thread, length 9.5 mm (unfortunately not in your list). I need 20-30 pieces initially. The reason is that we are a metric lab but we have started to use MiniSeries and decided to reuse your standard 6 mm diameter cage rods as posts in MiniSeries, instead of buying separate 6 mm diameter MiniSeries posts (which would add clutter and confusion in the lab as new students try to interchange them with the cage rods). Its quite strange that this thread adapter is not a stock item, given your wide assortment. Right now we have to use two thread adapters on top of one another to mount an M4-threaded component to a cage rod; we have also tried to double-tap M4 holes with #8-32 tap to make it fit a single thread adapter, but I doubt the latter is a good idea lab-wide.
apalmentieri  (posted 2010-02-17 15:15:44.0)
A response from Adam at Thorlabs to Hanneke: We are currently in the process of evaluating the packaging of all of our products. We are updating the packaging to make them more environmentally friendly. Thank you for the suggestions, I agree that this is a good idea and we will get started on changing this packaging.
hanneke  (posted 2010-02-17 12:20:53.0)
I just ordered a bunch of thread adapters and have spent the morning unwrapping each individual screw. It seems that you could save yourself money and your customers time by putting the screws in ziplock bags based on part number in the quantity ordered (e.g. all the AP6M8E screws in the same bag). I do appreciate the perforations on the baggies, though.
Laurie  (posted 2008-10-15 12:01:49.0)
Response from Laurie at Thorlabs to dsmith: It is possible for our machine shop to do some custom machining, but we would need you to provide us with a drawing of your exact requirements prior to quoting you the cost. Thanks for your interest in our products, and please let us know if we can be of further assistance.
dsmith  (posted 2008-07-18 07:14:57.0)
I am looking for an adapter for use on an angle grinder with a 5/8" female thread to attach an M14 internally threaded cone. I would be looking for a quantity of approx. 50 pcs. Any assistance would be appreciated. Best Regards, Darragh Smith Technical Sales Abcon Industrial Products Cavmac Hose Building Cavan Road Cootehill Co Cavan Ireland

Thread Adapters - External to External

Item # Thread A
(External)
Thread B
(External)
Length C
Imperial Thread Adapters
AP8E4Ea 8-32 4-40 0.38" (9.7 mm)
AP8E25Ea 8-32 1/4"-20 0.57" (14.5 mm)
Imperial/Metric Thread Adapters
AP8E4Ma,b 8-32 M4 x 0.7 0.48" (12.2 mm)
AP25E6Ma,b 1/4"-20 M6 x 1.0 0.57" (14.5 mm)
AP6M8Ea,b M6 x 1.0 8-32 0.57" (14.5 mm)
Metric Thread Adapters
AP4M3Mb M4 x 0.7 M3 x 0.5 0.38" (9.7 mm)
AP6M4Mb M6 x 1.0 M4 x 0.7 0.57" (14.5 mm)
  • This adapter is included in the HW-KIT6 Imperial Screw Thread Adapter Kit.
  • This adapter is included in the HW-KIT6/M Metric Screw Thread Adapter Kit.
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
AP8E4E Support Documentation
AP8E4EAdapter with External 8-32 Threads and External 4-40 Threads
$1.98
Today
AP8E25E Support Documentation
AP8E25EAdapter with External 8-32 Threads and External 1/4"-20 Threads
$1.98
Today
+1 Qty Docs Part Number - Universal Price Available / Ships
AP8E4M Support Documentation
AP8E4MCustomer Inspired! Adapter with External 8-32 Threads and External M4 x 0.7 Threads
$1.98
Today
AP25E6M Support Documentation
AP25E6MAdapter with External 1/4"-20 Threads and External M6 x 1.0 Threads
$1.98
Today
AP6M8E Support Documentation
AP6M8EAdapter with External M6 x 1.0 Threads and External 8-32 Threads
$1.98
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
AP4M3M Support Documentation
AP4M3MAdapter with External M4 Threads and External M3 Threads
$1.98
Today
AP6M4M Support Documentation
AP6M4MAdapter with External M6 x 1.0 Threads and External M4 x 0.7 Threads
$1.98
Today

Thread Adapters - Internal Threading with External Threaded Stud

Item # Thread A
(Internal)
Thread B
(External)
Length C Outer Diametera
Imperial Thread Adapters
AS6E8E 6-32 8-32 0.56" (14.2 mm) 0.24" (6.0 mm)
AS8E25Eb 8-32 1/4"-20 0.68" (17.3 mm) 0.40" (10.2 mm)
AS25E8Eb 1/4"-20 8-32 0.61" (15.4 mm) 0.40" (10.2 mm)
Imperial/Metric Thread Adapters
AS8E4M 8-32 M4 x 0.7 0.56" (14.2 mm) 0.25" (6.4 mm)
AS8E6M 8-32 M6 x 1.0 0.68" (17.3 mm) 0.40" (10.2 mm)
AS25E4M 1/4"-20 M4 x 0.7 0.61" (15.4 mm) 0.40" (10.2 mm)
AS25E6M 1/4"-20 M6 x 1.0 0.63" (16.0 mm) 0.38" (9.5 mm)
AS4M8E M4 x 0.7 8-32 0.56" (14.2 mm) 0.25" (6.4 mm)
AS4M25E M4 x 0.7 1/4"-20 0.68" (17.3 mm) 0.40" (10.2 mm)
AS6M8E M6 x 1.0 8-32 0.61" (15.4 mm) 0.40" (10.2 mm)
AS6M25E M6 x 1.0 1/4"-20 0.63" (16.0 mm) 0.38" (9.5 mm)
Metric Thread Adapters
AS4M6Mc M4 x 0.7 M6 x 1.0 0.68" (17.3 mm) 0.40" (10.2 mm)
AS6M4Mc M6 x 1.0 M4 x 0.7 0.61" (15.4 mm) 0.40" (10.2 mm)
  • This is the outer diameter of the internally threaded section.
  • This adapter is included in the HW-KIT6 Imperial Screw Thread Adapter Kit.
  • This adapter is included in the HW-KIT6/M Metric Screw Thread Adapter Kit.
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
AS6E8E Support Documentation
AS6E8EAdapter with Internal 6-32 Threads and External 8-32 Threaded Stud
$4.27
Today
AS8E25E Support Documentation
AS8E25EAdapter with Internal 8-32 Threads and External 1/4"-20 Threaded Stud
$4.27
Today
AS25E8E Support Documentation
AS25E8EAdapter with Internal 1/4"-20 Threads and External 8-32 Threaded Stud
$4.27
Today
+1 Qty Docs Part Number - Universal Price Available / Ships
AS8E4M Support Documentation
AS8E4MAdapter with Internal 8-32 Threads and External M4 x 0.7 Threaded Stud
$4.27
Today
AS8E6M Support Documentation
AS8E6MAdapter with Internal 8-32 Threads and External M6 x 1.0 Threaded Stud
$4.27
Today
AS25E4M Support Documentation
AS25E4MAdapter with Internal 1/4"-20 Threads and External M4 x 0.7 Threaded Stud
$4.27
Today
AS25E6M Support Documentation
AS25E6MAdapter with Internal 1/4"-20 Threads and External M6 x 1.0 Threaded Stud
$4.27
Today
AS4M8E Support Documentation
AS4M8EAdapter with Internal M4 x 0.7 Threads and External 8-32 Threaded Stud
$4.27
Today
AS4M25E Support Documentation
AS4M25EAdapter with Internal M4 x 0.7 Threads and External 1/4"-20 Threaded Stud
$4.27
Today
AS6M8E Support Documentation
AS6M8EAdapter with Internal M6 x 1.0 Threads and External 8-32 Threaded Stud
$4.27
Today
AS6M25E Support Documentation
AS6M25EAdapter with Internal M6 x 1.0 Threads and External 1/4"-20 Threaded Stud
$4.27
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
AS4M6M Support Documentation
AS4M6MAdapter with Internal M4 x 0.7 Threads and External M6 x 1.0 Threaded Stud
$4.27
Today
AS6M4M Support Documentation
AS6M4MAdapter with Internal M6 x 1.0 Threads and External M4 x 0.7 Threaded Stud
$4.27
Today

Dual Threaded Adapter - Internal to External

Item # Thread A
(Internal)
Thread B
(External)
Length C
Imperial Thread Adapters
AE4E25Ea 4-40 1/4"-20 0.38" (9.5 mm)
AE6E25E 6-32 1/4"-20 0.38" (9.5 mm)
AE8E25Ea 8-32 1/4"-20 0.38" (9.5 mm)
Imperial/Metric Thread Adapters
AE4E6M 4-40 M6 x 1.0 0.39" (10.0 mm)
AE6E6M 6-32 M6 x 1.0 0.39" (10.0 mm)
AE8E6M 8-32 M6 x 1.0 0.39" (10.0 mm)
AE3M25E M3 x 0.5 1/4"-20 0.38" (9.5 mm)
AE4M25E M4 x 0.7 1/4"-20 0.38" (9.5 mm)
Metric Thread Adapters
AE3M6Mb M3 x 0.5 M6 x 1.0 0.39" (10.0 mm)
AE4M6Mb M4 x 0.7 M6 x 1.0 0.39" (10.0 mm)
  • This adapter is included in the HW-KIT6 Imperial Screw Thread Adapter Kit.
  • This adapter is included in the HW-KIT6/M Metric Screw Thread Adapter Kit.
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
AE4E25E Support Documentation
AE4E25EAdapter with Internal 4-40 Threads and External 1/4"-20 Threads
$4.27
Today
AE6E25E Support Documentation
AE6E25EDual Threaded Adapter with Internal 6-32 Threads and External 1/4"-20 Threads
$4.27
Today
AE8E25E Support Documentation
AE8E25EDual Threaded Adapter with Internal 8-32 Threads and External 1/4"-20 Threads
$4.27
Today
+1 Qty Docs Part Number - Universal Price Available / Ships
AE4E6M Support Documentation
AE4E6MDual Threaded Adapter with Internal 4-40 Threads and External M6 x 1.0 Threads
$4.27
Today
AE6E6M Support Documentation
AE6E6MDual Threaded Adapter with Internal 6-32 Threads and External M6 x 1.0 Threads
$4.27
Today
AE8E6M Support Documentation
AE8E6MDual Threaded Adapter with Internal 8-32 Threads and External M6 x 1.0 Threads
$4.27
Today
AE3M25E Support Documentation
AE3M25EDual Threaded Adapter with Internal M3 x 0.5 Threads and External 1/4"-20 Threads
$4.27
Today
AE4M25E Support Documentation
AE4M25EDual Threaded Adapter with Internal M4 x 0.7 Threads and External 1/4"-20 Threads
$4.27
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
AE3M6M Support Documentation
AE3M6MAdapter with Internal M3 x 0.5 Threads and External M6 x 1.0 Threads
$4.27
Today
AE4M6M Support Documentation
AE4M6MDual Threaded Adapter with Internal M4 x 0.7 Threads and External M6 x 1.0 Threads
$4.27
Today

Thread Adapters - Internal to Internal

Item # Thread A
(Internal)
Thread B
(Internal)
Length C Outer Diameter
AI25E8E 8-32 1/4"-20 0.50" (12.7 mm) 0.40" (10.2 mm)
AI6M4M M4 x 0.7 M6 x 1.0 0.50" (12.7 mm) 0.40" (10.2 mm)
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
AI25E8E Support Documentation
AI25E8EAdapter with Internal 1/4"-20 Threads and Internal 8-32 Threads
$4.90
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
AI6M4M Support Documentation
AI6M4MAdapter with Internal M6 x 1.0 Threads and Internal M4 x 0.7 Threads
$4.90
Today

Mini-Series Thread Adapters

MSA8 Application
Click to Enlarge
The MSA8 Mini-Series Thread Adapter Converts an 4-40-Threaded Stud into an 8-32-Threaded Stud
  • Machined from Stainless Steel
  • Adapts to Other Common Thread Standards
Item # Thread A
(Internal)
Thread B
(External)
Length C Outer Diametera
MSA8 4-40 8-32 0.50" (12.7 mm) 0.40" (10.2 mm)
MSA25 4-40 1/4"-20 0.55" (14.0 mm) 0.50" (12.7 mm)
MSA4/M M3 x 0.5 M4 x 0.7 0.50" (12.7 mm) 0.40" (10.2 mm)
MSA6/M M3 x 0.5 M6 x 1.0 0.55" (14.0 mm) 0.50" (12.7 mm)
  • This is the outer diameter of the internally threaded section.
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
MSA8 Support Documentation
MSA8Mini-Series Adapter with External 8-32 Threads and Internal 4-40 Threads
$5.10
Today
MSA25 Support Documentation
MSA25Mini-Series Adapter with External 1/4"-20 Threads and Internal 4-40 Threads
$5.10
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
MSA4/M Support Documentation
MSA4/MMini-Series Adapter with External M4 Threads and Internal M3 Threads
$5.10
Today
MSA6/M Support Documentation
MSA6/MMini-Series Adapter with External M6 Threads and Internal M3 Threads
$5.10
Today

Threaded Counterbore Adapters

  • Converts a Counterbored Clearance Hole into a Tapped Hole
  • Slotted Edge for Tightening
  • Designed for Slip Fit with Thorlabs' Counterbores

Threaded counterbore adapters are used to convert a counterbore into a threaded hole. A part such as the KM100 Kinematic Mirror Mount features a counterbore that provides imperial and metric compatibility; a cap screw is typically used to fasten the mount to a post. In some instances, it may be necessary to attach the mount to a post with a fixed threaded stud. The counterbore adapter facilitates this mounting option. These adapters feature a slotted edge that enables tightening or removal.

Item # Thread A
(Internal)
Outer Diameter B Use in C-Bore
CBA8E 8-32 0.28" (7.0 mm) #8
CBA25E 1/4"-20 0.40" (10.2 mm) 1/4"
CBA4M M4 x 0.7 0.28" (7.0 mm) M4
CBA6M M6 x 1.0 0.40" (10.2 mm) M6
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
CBA8E Support Documentation
CBA8E8-32 Tapped Counterbore Adapter
$7.50
Today
CBA25E Support Documentation
CBA25E1/4"-20 Tapped Counterbore Adapter
$7.50
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
CBA4M Support Documentation
CBA4MM4 x 0.7 Threaded Counterbore Adapter
$7.50
Today
CBA6M Support Documentation
CBA6MM6 x 1.0 Threaded Counterbore Adapter
$7.50
Today

Counterbore Adapter Rings

SD1 Adapter Ring in RC1 Rail Carrier
Rail Carrier Cross Section with SD1 Counterbore Adapter Ring
  • Allows a #8 (M4) cap screw to be used within a 1/4" (M6) counterbore
  • Solid stainless steel design
  • Sold in packages of 10

The SD1 adapter ring allows a #8 (M4) cap screw to be used within the 1/4" (M6) counterbore of many parts including rail carriers, BA2 mounting bases, etc. Most of our optomechanical components, such as our compact mirror mounts, feature tapped 8-32 (M4) holes, which this adapter is designed for. For example, the VC1 small V-clamp can mount directly to a BA1 base when an SD1 adapter is used with a 8-32 cap screw.

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available / Ships
SD1 Support Documentation
SD11/4" (M6) Counterbore Adapter Ring for 8-32 (M4) Screws, 10 per Pack
$7.91
Today

Screw Thread Adapter Kit

HW-KIT6 Imperial Thread Adapter Kit
Item Qty. Item Qty.
External 8-32 and External 1/4"-20 (AP8E25E) 5 External 8-32 and External M4 x 0.7 (AP8E4M) 5
Internal 8-32 and External 1/4"-20 (AS8E25E) 5 External 8-32 and External 4-40 (AP8E4E) 5
External M6 x 1.0 and External 1/4"-20 (AP25E6M) 5 External 8-32 and Internal 1/4"-20 (AS25E8E) 5
External 8-32 and External M6 x 1.0 (AP6M8E) 5 Internal 4-40 and External 1/4"-20 (AE4E25E) 5
Internal 8-32 and External 1/4"-20  (AE8E25E) 10 - -
HW-KIT6/M Metric Thread Adapter Kit
Item Qty. Item Qty.
External M4 x 0.7 and External M6 x 1.0 (AP6M4M) 5 External 8-32 and External M4 x 0.7 (AP8E4M) 5
Internal M4 x 0.7 and External M6 x 1.0 (AS4M6M) 5 External M4 x 0.7 and External M3 x 0.5 (AP4M3M) 5
External M6 x 1.0 and External 1/4"-20 (AP25E6M) 5 External M4 x 0.7 and Internal M6 x 1.0 (AS6M4M) 5
External 8-32 and External M6 x 1.0 (AP6M8E) 5 Internal M3 x 0.5 and External M6 x 1.0 (AE3M6M) 5
Internal M4 x 0.7 and External M6 x 1.0 (AE4M6M) 10 - -
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Imperial Price Available / Ships
HW-KIT6 Support Documentation
HW-KIT6Imperial Screw Thread Adapter Kit
$130.56
Today
+1 Qty Docs Part Number - Metric Price Available / Ships
HW-KIT6/M Support Documentation
HW-KIT6/MMetric Screw Thread Adapter Kit
$130.56
Today
Log In  |   My Account  |   Contact Us  |   Careers  |   Privacy Policy  |   Home  |   FAQ  |   Site Index
Regional Websites: West Coast US | Europe | Asia | China | Japan
Copyright 1999-2018 Thorlabs, Inc.
Sales: 1-973-300-3000
Technical Support: 1-973-300-3000


High Quality Thorlabs Logo 1000px:Save this Image