"A versatile tool for any gun owner, Lyman A-Zoom Snap Caps withstand thousands of dry fires while protecting your gun's firing pin. Great for adjusting and tuning trigger pull, offhand dry firing, cycling practice, gun safety instruction, and releasing mainspring tension during storage, A-Zoom Snap Caps are precision machined from aluminum to exacting tolerances. A hard anodized finish provides smooth functioning and long cycling life. The durable ""Dead Cap"" design is proven to withstand over 3,000 dry fires while protecting the firing pin, lasting 30 times longer than conventional plastic counterparts. Available in rifle, shotgun, handgun, and rimfire cartridges. Durable aluminum construction Hard anodized finish Durable ""Dead Cap"" design Protects firearm's firing pin during practice, training, maintenance, or storage Great for tuning trigger pull, cycling practice, gun safety training, and releasing mainspring tension during storage"