Turning Point - Express Mach4 Stainless Steel Propeller - Left Hand - 4-Blade - 14" x 21 Pitch - EX-1421-4L - 31502141. The Prop that put the "four" in Perfourmance! Turning Point's Four Blade revolutionized the propeller market when it was introduced. No one had ever produced a propeller with two different blade shapes (they call it Dual Geometry) for 90-300+hp applications. This prop is uniquely engineered with two blade geometries: (diagram label 2)two blades utilize the Hustler high performa