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Library › Hardware › Hex lag screws 5/8, 3/4, 7/8 and 1 in (ASME B18.2.1): head width and…

1 hex lag screw envelope

1 hex lag screw envelope: hex head 1.5 in across flats (basic) × 0.6719 in high (basic) on a plain Ø25.40 mm (1 in nominal) shank, example length 4 in (101.6 mm) under the head (Xem's choice); no thread, chamfer, washer face or point

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

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From the full sheet

Hex lag screws 5/8, 3/4, 7/8 and 1 in (ASME B18.2.1): head width and height, shank, pilot holes + envelope models: every size, notes, mating features and sources. What size is the head of a 3/4 lag screw, and what pilot hole does a 5/8 lag bolt need?

Other sizes