BLACK PROJECT HAMMER GT SLALOM & RACING FINHAMMER GT Slalom & Racing Fin Power, Acceleration & Control Slalom Fin The Hammer GT Slalom Race windsurfing fin is our elite level racing and slalom foil. Building on the success and extensive testing of the Type R we worked for more than two years to make something better. The Hammer was designed to give ultimate grip and control in a slightly more compact and powerful outline than the original Type R. This is a heavy hitting and powerful fin and