The 2 Blade Mechanical Replacement Kit for the Tooth of the Arrow 2 Blade Mechanical Broadhead. Each replacement kit comes with the following: 6 premium stainless steel blades 6 all weather o-rings 3 heat treated, high carbon steel screws The 2 Blade Mechanical Replacement Kit works with both 100 grain and 125 grain Tooth of the Arrow 2 Blade Mechanical Broadheads.