PRODUCT OVERVIEW:Use the Scotty Backing Plate to add structural support when attaching the Scotty No. 241L or No. 241 Combination Side/Deck Mounts or the No.244L or 244 Flush Deck Mounts to a thin-walled watercraftMade with super tough, rugged engineering grade nylonIncludes stainless steel nuts & machine screws(Stainless steel Nylock nuts are retained in plate for ease of installation)Mount Dimensions:4 x 2Bolting Dimension:1 5/16 x 3 3/16WARNING: Cancer and Reproductive Harm -www.P65Warnings.ca.gov