This amazing twin-propeller, contra-rotating system is the ultimate performance upgrade for boats with Volvo Penta DPS drives. A large diameter four-blade front propeller coupled with a smaller diameter, three-blade rear propeller provide both faster acceleration and better top speed than original equipment F series propellers. Matte finish. Vendor Part Number: 710-48-8M8026210 Larger diameter for exceptional performance Fast acceleration & better top speed | Quicksilver Thunderbolt DPS 4-Bl Propeller / SS, 16 dia x 19, LH