ITEM NAME:2 Sets Stainless Steel Fin Board Surfboard Longboard Screw & Plate Description: 316 stainless steel construction, rust and corrosion resistant. A rubber O-ring to eliminate loosening while surfing. No Tool Required: Hand tighten against rubber o-ring, easy to install in seconds. Fits all standard fin boxes in the market. A perfect and must-have replacement fit for long board surfers. Specification: Material: 314 stainless Steel Color: Silver Model: M4 Thread Length: 19mm/0.75inch Package Includes: 2 Sets Screws Note: Due to the difference between different monitors, the picture may not reflect the actual color of the item. Due to manual measurement, there may be 1-2mm error in size. SKU: DMO0001310354029282.Fits all standard fin boxes in the market. A rubber O-ring to eliminate loosening while surfing. 316 stainless steel construction, rust and corrosion resistant. Material: 314 stainless Steel. No Tool Required: Hand tighten against rubber o-ring, easy to install in seconds.