Gravity locks automatically open when wheelie bins are tipped up for emptying. They are easy to install using the drilling template and instructions that are supplied.A Gravity Lock is a dumpster with an accompanying bar that is to remain in the locked position when servicing the dumpster. Gravity releases the lock when the dumpster is being tipped over during service.A Gravity Lock is a dumpster with an accompanying bar that is to remain in the locked position when servicing the dumpster. Gravity releases the lock when the dumpster is being tipped over during service. The gravity lock is designed to be used in combination with a padlock lock you provide.