VisuaLock is a gun safety device that provides 100-percent security to a firearm with a loaded magazine or remaining cylinders loaded. When properly installed, the firearm cannot be fired. To use, the Security Cartridge is inserted in place of a live round. The Security Rod is then placed down the barrel and locked into the Security Cartridge by placing the VisuaLock Key into the end of the Security Rod, pushing in and turning a quarter of a turn clockwise. Only the firearm owner with the special VisuaLock key can remove the safety and use the firearm for self defense. VisuaLock is California Certified and is available in 9mm, 40S'W, 45ACP, 357/38 Special and .22 calibers. Other calibers can be provided on request. Barrel lengths from 3 inches to 5 inches are covered by the standard length safety rod, and the long length rod covers lengths from 5 inches to 7 inches. Longer lengths can be provided on request.