VIRTUALLY BURGLAR PROOF - Are you worried that someone might break into your house at the middle of the night or sometime of the day when nobody is home? Well that problem is no longer an issue. With its double locking action, it is virtually impossible to remove the door by lifting it off its track. The Cal Double Bolt patio door lock prevents criminals from being able to lift out sliding glass doors from their tracks.DISCOVER NEW WAYS TO INCREASE CHILDREN SECURITY - With young children in the home, you know all too well how hard it is to keep an eye on them at all times. With the Cal Double Bolt child proof patio door lock installed, you can make sure that young ones do not become tempted to open the sliding glass doors on their own and expose themselves to potential danger.100% MONEY BACK GUARANTEED - If the Cal Double Bolt Lock does not meet up to your standards, we will be more than happy to refund you. We value our customers more than anything.KEEP YOUR FAMILY AND CHILDREN SAFE - The double bolt lock can function in a way to keep your family and children safe. The lock can easily be mounted above the OEM lock to be out of childrens reach. Additionally the Cal Double Bolt sliding door lock is clearly visible whether the lock is engaged or not, so it is more likely that parents will keep it in the locked position.NO NEED TO WASTE HOURS OF SETTING UP - The CAL Double Bolt Lock has a sleek, aesthetic, low profile design. As a result, the sliding glass door lock fits easily within the limited space available between the sliding glass door frame and the interior of the door panel. This amazingly simple device is EASY TO INSTALL and has been tested to provide over 1000 lbs of Forced Entry Load Tension. An easy step by step instructions are also included with the product.