SATISFIED SERVICES & PROTECT YOUR FAMILY SAFE: CALDEVER always insists on providing high-quality products and professional after-sales. If you have any questions, we're standing by to assist you all the time for your better purchase experience. Our reliable window lock effectively reduces the risk of children & pets falling from heights, and guards against theft, protects your property against damage during heavy rains and hurricanes, it's also great for people who live alone. You deserved it!Upgraded Home Security Lock for Sliding Doors & Window: If you are concerned that your window and doors are not sturdy enough, CALDEVER heavy-duty sliding door lock provides added security and childproof lock safety, secure as extra door locks for the front door, sliding glass door lock, patio door lock, window locks for both vertical and horizontal sliding Windowan extra layer of security for apartment essentials and home safety. CALDEVER sliding door locks, protect yourself and your familyQUICK & EASY TO INSTALL, SAVE TIME & EFFORT: No need for extra installation tools or drilling required 3-step quick installation. Just place the lock in a suitable position and tighten the screws! The removable rubber lining can help us have two flexible ways to lock the window or doors. But the rubber lining is useful for reducing window tracks' scratches and damage. 10 sets of safe window locks can reuse, and even women or the elderly can also easily complete this installation process alone.ADJUSTABLE SCREW LOCKS, HIGH DURABILITY & STABILITY: This upgraded window double lock is made of solid and reliable aluminum alloy with exquisite workmanship, is more secure, and can serve you for a long time using. You can fix the window in place so can't be pulled or opened, and multiple locks can be applied at the same time to various window or doors to increase safety. You will be so happy these secondary locks can increase your home's safety.Super Easy to Install: Mount the door lock security at the top/bottom(2 options) rail of the slider doors/window, apartment must haves CALDEVER sliding door lock with fully or partially locked options, you can use it as a standard door lock, or lock it with the door partially open as door stoppers to let fresh in, ventilation gaps are not large enough for kids to pass through, door locks for kids safety home essentials. CALDEVER safety locks for doors guard your home security as a door defender