Killzone Crossbow Replacement Blades (6-Pack), 100/125-Grain 100/125 grain, 6 pack 2" cutting diameter Replacement blades Spring clip design - No 0-rings or rubber bands Heavy-duty, razor-sharp .039" blades Features patented "Spring Clip" blade retention system to keep blades closed in flight 2" cutting diameter for devastating wound channels & excellent penetration Heavy-duty, Razor-sharp .039" blades Designed for use out of crossbows up to 400 fps