Dorsal Center Fin Surf SUP Longboard Surfboard Fins - Screw Plate Set of 2 / Stainless TIME TESTED DESIGN: 1,2,3 Pack of Stainless Steel Longboard and SUP fin screws. Usage: Slide in fin box, insert fin, put screw in, tighten with slotted screw driver. UNIVERSAL FIT: Fits All Standard Fin Boxes. Plate is .55"x.55"x .15" (14mm x 14mm x 4mm). Screw is 10-32 X 3/4"(5mm x 19mm) Long. HIGH QUALITY MATERIALS: 316 Stainless Steel Plate and 18-8 Stainless Steel Screw. WILL NOT RUST 5% TO CHARITY: Every month we send 1% of our sales to a charity. This month it is El Camino which is improving the health, eternal well being and self-reliance of children living in isolated regions or Peru.