Hi-Tech Fasteners Inc.
Hi-Tech Fasteners, Inc.
4940 Winchester Boulevard
Frederick, Maryland 21703-7400

Toll Free: 800.466.1940
Tel: 301.831.1277
Fax: 301.831.8296
Email: sales@hitechfasteners.com
Website: www.hitechfasteners.com
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Locking and Non-locking Threads
These fasteners provide load-bearing threads in thin sheets and permit up to .030” adjustment for mating  hole misalignment.

The self-clinching feature offers fast and simple assembly. The fasteners are squeezed into prepared holes using  any standard press. The sheet remains flush on one side, and the fastener is permanently locked in place.

Extra strength and support in assembly is obtained by the threads of the floating nut extending fully into the  retainer shank (a unique PEM feature). A self-locking version of the fastener is also offered. Thread locking torque  performance is equivalent to applicable NASM25027 specifications.

Non-locking Type A4 and self-locking Type LA4 fasteners provide load-bearing threads in stainless steel sheets  as thin as .038” with hardness up to HRB 88 on the Rockwell “B” scale.

Many PEM Type AS and AC self-clinching floating fasteners correspond to sizes in US NASM45938/11 specifications. Check our  web site for a complete Military Specification and National Aerospace Standards Reference Guide (Bulletin NASM).
Unit of Measure

Specifications

Thread Size

 N/A .250-28 (1/4-28)

Thread Type

 N/A Non-Locking a1369_1.jpg

Thread Code

 N/A 0428
Shank Code1 N/A 2

A (Shank) Max.

 N/A .054 in a1367_1.jpg

Min. Sheet Thickness

 N/A .054 in

Hole Size in Sheet + .003 - .000

 N/A .515 in

C Max.

 N/A .514 in

D Max.

 N/A .510 in

E ± .015

 N/A .600 in

T1 Max.

 N/A .210 in
Min. Dist. Hole C/L to Edge2 N/A .420 in

Float

 N/A .015” minimum, in all directions from center, .030” total

Fastener Material

 N/A 300 Series Stainless Steel

Fastener Materials - Retainer

 N/A 300 Series Stainless Steel

Fastener Materials - Nut

 N/A 300 Series Stainless Steel

Standard Finish - Retainer & Nut

 N/A Passivated and/or tested per ASTM A380
For Use in Sheet Hardness3 N/A HRB 70 / HB 125 or Less

Thread Specification

 N/A Internal, ANSI B1.1, 2B

CAD Supplier

 N/A PennEngineering® (PEM®)

Inventory

 N/A {0}
  • 1 Other shank and screw lengths available.
  • 2 To minimize sheet distortion and maximize product performance, use a centerline-to-edge value greater or equal to the value specified.
  • 3 HRB - Hardness Rockwell “B” Scale. HB - Hardness Brinell.