●🏄♂️ SET OF 2 FINS can be used as SIDE BITES for longboards, or REAR TRAILER FINS for a quad fin setup. For Single Tab fins, longboards usually use the 3/4" base size, while quad trailer fins are usually 1/2" base. Check your fin box depth before ordering. Twin Tab only has one size, and can be used for longboard setup and quad fin setup. ●🌊 Sidebite fins add POWER, DRIVE, and STABILITY to your single fin setup. Or turn your thruster setup into a QUAD setup, using these fins as your rear trailer fins. ●🔩 EVERYTHING YOU NEED - Set includes 2 Side Bite Fins, fin key, and screws. So you can get back in the water fast! ●💪 FRP (Fiberglass Reinforced Polymer) material combines fiberglass with polymer to create DURABLE and STRONG side bite fins with LESS FLEX than standard nylon plastic fins. ●💯 100% SATISFACTION GUARANTEE: As with all of our surf gear, if you are not completely satisfied for ANY reason, simply return your Side Bite Fins within 30 days for a full refund.