FCS II Pivot PG Longboard Fin - Performance Glass single fin FCS II Pivot Performance Glass 10 inch Longboard fin. Upright fin with minimal sweep and base. Loose fin for performing tighter turns. Performance Glass (PG) material characteristics and flex pattern are identical to traditional fiberglass fins offering a stiff base with subtle responsive tip flex, amazing aesthetics and proven durability. 2 + 1 Compatible. Suits most longboards with hard edges. Designed to be used in most existing FCS Longboard boxes. No new box