Designed by Dan Mann, the Firewire template is suited to Firewire surfboards. The full-bodied XL side fins produce exceptional hold and drive off the bottom and the smaller center fin and unique tip design offers the projection of a twin with a surprising amount of release through turns.Performance Core material and construction is designed to deliver the feeling of a traditional fiberglass fin with the added performance of reduced weight. The side fins have a 4.34" base and 4.75" depth. The center fin has a 4.26" base and 4.45" depth.