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hex cap screw 1-3/8-6 UNC envelope

hex cap screw 1-3/8-6 UNC envelope: hex head 2.062 in across flats x .878 in high (F max, H max), plain shank Ø1.3750 in (major diameter, thread not drawn), 4 in under the head (example length, Xem choice); published thread length LT 3.000 in (L ≤ 6 in)

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

stylehex cap screw
size (in)1-3/8
UNC / UNF TPI6 / 12
E body dia max / min1.3750 / 1.3630
F across flats max / min2.062 / 1.994
G across corners max / min2.382 / 2.273
H head height max / min.878 / .810
J wrenching height min (cap only).569
LT thread length, L ≤ 6 in3.000
LT thread length, L > 6 in3.250
file: F max / H max (mm)52.37 / 22.3
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From the full sheet

Hex cap screws and heavy hex screws, inch 7/8 to 1-1/2 (ASME B18.2.1): across flats F, head height H, thread length LT: every size, notes, mating features and sources. What are the head size, head height and thread length of a 7/8, 1, 1-1/8, 1-1/4, 1-3/8 or 1-1/2 inch hex cap screw or heavy hex screw?

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