Shakespeare Style 4187-HDEXTRA HEAVY-DUTY RATCHET MOUNT STAINLESS STEELVersatile four-way ratchet design for deck or side mounting. Quick-action handle makes operation easy. Standard 1"-14 thread. The Style 4187-HD adds extra strength and rigidity.Use wherever its extra heavy-duty construction is needed. Standard 1"-14 thread.9/32" hole for cable feed-throughBolt holes: 5/16" dia., 3" x 1-1/2" on center - cis2:mm5mnJlm -Specifications: Type: Mounting Brackets; Box Dimensions: 3"H x 7"W x 10"L WT: 2.2 lbs; UPC: 719441110239; Quick Guide (pdf)