Want some extra peace of mind for your sliding doors or windows? These Artoshin security bars are a simple, super effective solution. You get 4 bars in the pack, and each one can adjust from about 23.6 inches all the way up to 43.3 inches, so they'll fit a wide range of window and door widths. They work on a simple tension principle – you just twist them to extend them until they're snug between the frame and the sliding panel. The ends have rubber tips to grip and not damage your surfaces. They're made from sturdy carbon steel with a white painted finish, and best of all, they require NO DRILLING to install. Just put them in place and twist. They act as a physical barrier to stop intruders from forcing the door open, and they're also great for child safety to prevent little ones from opening windows or doors they shouldn't. Super easy to use and remove when you need to. A smart, affordable way to boost your home security.