3 fins that are Single Tab compatible; Surf Twin Fin Set + Trailer Fin (2+1 Fins) - Solid Fiberglass and Nylon - for Single Tab Surf Boards, Shortboard Twin fins with a small stabilizer (center fin) which adds control while maintaining maneuverability of a twin fin setup; You can use with or without the stabilizer fin; Perfect for fish and twin fin model surfboards. Nylon and Fiberglass strongest fin construction and has the best flex; The fins have a smooth finish, ensuring a fast surface. Twin fins are flat foil - Base: 133mm & 5.236 inch, Height: 135mm & 5.315 inch Trailer Fin is double foil - Base: 89mm & 3.5 inch, Height: 86mm & 3.386 inch Applicable People: Unisex Outdoor Activity: Water Sport Surfing Model: Single tab base Outdoor Activity: Surfboard Accessories Color: Black Material: Nylon + Glass Fiber Package Contents: 1 x Surfboard Fins kit (3 pcs) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item to appear slightly different from the real thing. The measurement allowed error is +/- 1-3 cm.