Strut fittings are made from 1/4" thick by 1 5/8" wide 316SS stock. Part Number Hole Diameter 5970 - 1/4 5/16" (for use with 1/4" bolt) 5970 - 3/8 7/16" (for use with 3/8" bolt) 5970 - 1/2 9/16" (for use with 1/2" bolt) 5970 - 5/8 11/16" (for use with 5/8" bolt)