This product is amazing – SO SIMPLE and works great! The strap latch keeps the door from opening too much, which will allow cats in but keep larger dogs and babies out. The stopper keeps the door from closing all the way, keeping finger safe and stopping cats from getting locked in a room. This enables you to give cats access to a room where their litterboxes and food are out of reach from dogs and kids, or as a safe space where they can just peacefully enjoy being alone.