PROLOCK Propane Safety Cap is child-resistant and tamper resistant; it prevents anyone including children from accessing or turning on the valve on the propane tank. PROLOCK is very simply, easy to use, comes in very clear, self-explanatory packaging, and addresses a critically needed area. PROLOCK comes with a high-quality lock, two keys, and a distinctive key chain, the key chain acts as a visual reminder to secure your tank. PROLOCK Propane Safety Cap installs in seconds!