PEM® brand miniature fasteners fit into a minimal space and provide strong, reusable threads.
Types FE, FEO and UL are self-locking. Types FE and FEO thread locking torque performance is equivalent to applicable NASM25027 specifications. Type UL self-locking nuts meet locking torque requirements specified herein. Some sizes of FE, FEO, and UL can be ordered to NASM45938/7 specifications. Types FEX, FEOX and U have free-running class 2B/6H threads.
PEM miniature fasteners provide immediate visual indication when proper installation has been accomplished.
A strong, knurled collar, which is completely embedded in the sheet, guarantees against rotation of the fastener in the sheet. The torque-out resistance of the knurl greatly exceeds the torque that can be exerted by the selflocking feature.
When this collar is embedded in the sheet, the undercut cavity beneath the collar is filled with displaced sheet material thereby developing pushout resistance.
A dry-film lubricant applied to these fasteners provides the smooth, non-galling prevailing torque performance
necessary for reliable locking and for reusability.
Unit of Measure
Specifications
Thread Size
N/A.112-40 (#4-40)
Thread Type
N/ASelf-Locking
Thread Code
N/A440
A (Shank) Max.
N/A.040 in
Sheet Thickness1
N/A.039 to .045 in
Hole Size in Sheet + .003 - .000
N/A.172 in
C + .000 - .005
N/A.171 in
D Max.
N/A.145 in
E ± .005
N/A.192 in
T + .015 -.000
N/A.065 in
Min. Dist. Hole C/L to Edge
N/A.14 in
Max. Hole in Attached Parts
N/A.132 in
For Use in Sheet Hardness2
N/AHRB 70 / HB 125 or Less
Thread Specification
N/AInternal, MIL-S-8879, UNJ-3B
Fastener Material
N/A300 Series Stainless Steel
Standard Finish
N/ABlack, Dry-film Lubricant
CAD Supplier
N/APennEngineering® (PEM®)
1 In applications between the sheet thicknesses for your thread size, see last paragraph of installation data on page FE-6. Knurled collar may
fracture if fastener is used in sheets thicker than the specified range and the screw is tightened beyond maximum tightening torque.