Dimensions Guide
ESR-1078 
|
 Most Widely Accepted and Trusted  Page 3 of 8 
TABLE 1A—FASTENER SPECIFICATIONS: OLYLOG AND TIMBERLOK FASTENERS 
OLYLOG
®
/ 
TIMBERLOK
®
FASTENER 
DESIGNATION 
HEAD 
MARKING 
OVERALL 
LENGTH
1
(inches) 
LENGTH OF 
THREAD
2
(inches) 
UNTHREADED 
SHANK 
DIAMETER 
(inch) 
MINOR THREAD 
(ROOT) 
DIAMETER 
(inch) 
BENDING 
YIELD
3
(F
yb
, psi) 
ALLOWABLE 
FASTENER STRENGTH 
Tensile 
(lbf) 
Shear
4
(lbf) 
TLOK212 or LOG212 
F2.5 
2
1
/
2
1
1
/
4
0.189 
0.172 
167,300 
1,300 
940 
TLOK04 or LOG004 
F4.0 
4 
2 
190,600 
TLOK06 or LOG006 
F6.0 
6 
2 
TLOK08 or LOG008 
F8.0 
8 
2 
LOG009 
F9.0 
9 
2 
1,145 
800 
TLOK10 or LOG010 
F10.0 
10 
2 
LOG012 
F12.0 
12 
2 
LOG014 
F14.0 
14 
2 
LOG016 
F16.0 
16 
2 
For SI: 1 inch = 25.4 mm, 1 lbf = 4.4 N, 1 psi = 6.895 kPa. 
1
For purposes of measuring overall fastener length, fasteners must be measured from the underside of head to bottom of tip. 
2
Length of thread includes tip. See detailed illustration. 
3
Bending yield strength determined per methods specified in ASTM F1575 and based on the minor thread diameter. 
4
Allowable shear strength values apply only to shearing in the unthreaded shank portion of the fastener. 
TABLE 1B—FASTENER SPECIFICATIONS: HEADLOK FASTENERS 
HEADLOK
®
FASTENER 
DESIGNATION 
HEAD 
MARKING 
OVERALL 
LENGTH
1
(inches) 
LENGTH OF 
THREAD
2
(inches) 
UNTHREADED 
SHANK 
DIAMETER 
(inch) 
MINOR THREAD 
(ROOT) 
DIAMETER 
(inch) 
BENDING 
YIELD
3
(F
yb
, psi) 
ALLOWABLE 
FASTENER STRENGTH 
Tensile 
(lbf) 
Shear
4
(lbf) 
HLGM278 
F2.9HL 
2
7
/
8
2 
0.191 
0.172 
187,300 
1,215 
965 
HLGM412 
F4.5HL 
4
1
/
2
2 
HLGM6 
F6.0HL 
6 
2 
HLGM8 
F8.0HL 
8 
2 
HLGM10 
F10HL 
10 
2 
For SI: 1 inch = 25.4 mm, 1 lbf = 4.4 N, 1 psi = 6.895 kPa. 
1
For purposes of measuring overall fastener length, fasteners must be measured from the underside of head to bottom of tip. 
2
Length of thread includes tip. See detailed illustration. 
3
Bending yield strength determined per methods specified in ASTM F1575 and based on the minor thread diameter. 
4
Allowable shear strength values apply only to shearing in the unthreaded shank portion of the fastener.  










