HIGH-QUALITY MATERIAL: Surfboard screws are made of high-quality stainless steel, which is durable, rust-proof and anti-corrosion, good toughness, not easy to break, and supports long-term use of water in fresh water or salt water.SILICONE RING DESIGN: A black silicone ring is used between the screw and the bottom plate to make the surfboard screw more stable and prevent the surfboard fins from becoming loose under the impact of waves.EASY TO INSTALL: It can be tightened manually without any other tools, humanized design, just use your fingers to easily tighten the surfboard, you can fix the tail fin, saving time and effort.WIDE APPLICATION: Suitable for all standard, FCS, Futures surfboard fin boxes, suitable for longboard, SUP, inflatable SUP, single fin. Our products can bring you a wonderful experience when you surf.Delivery Quantity: 4pcs,Package Contents: Only the above package contents, excluding other products.Size: total length 30mm, thread length 19.4mm, thread diameter 3.5mm(Reminder: The size is measured manually, please allow 1-2 cm measurement error)Color: silver(Due to different monitors and lighting effects, the actual color of the item may be slightly different from the color shown on the picture.)