Machine Screw Type Suction Cups All sizes have 8 - 32 steel brass plated machine screws securely bonded to cups. Compare Item # Cup Diameter (A) Cup Height (B) Thread Length (C) Machine Screw Size SC-2125-01 2 1/8 in 3/4 in 1/2 in 8-32 SC-1750-01 1 3/4 in 5/8 in 3/8 in 8-32 SC-1375-01 1 3/8 in 1/2 in 3/8 in 8-32 SC-1000-01 1 in 7/16 in 1/4 in 8-32 Downloads Suction Cups and Vacuum Lifters Rubber Technical Information and Reference