This is a standard Garelick 75402:01 vessel side mount for a the table leg / grill stanchions. This comes with a 6 x 5 aluminum backing plate, the angled spacer (Yamaha PN F4X-U471E-00) four (4) stainless 1/4-20 x 2" fasteners, 4 stainless washers, and 4 ny-lock nuts.
PLEASE NOTE: This is for model year 2020 Model 275 and most 2021+ boats only (specific to the spacer).