The F-15 is the only broadhead with dual, side-byside cutting blades. The two razor-sharp blades give you 6 cutting edges and create a 250% greater wound opening than single blade broadheads. This means significantly greater blood loss, a better blood trail and ultimately, a faster kill. The F-15 is engineered to perform over and over with a patented process that uses 440 stainless steel and a Pressure Injected Mold (PIM). Its solid, one-piece construction makes it extremely durable. The blades in the F-15 Expandable are .030 inch thick for added strength and dependability. Expandable Blades.