What You Will Receive: package includes 20 pieces of window sash locks, comes with 32 pieces of screws; Sufficient quantity can meet your various uses and replacements in your daily life,Wide Uses: these window security locks can be applied for aluminum, wood and vinyl windows, suitable for vertical and horizontal sliding windows, single hanging and double hanging windows or doors,Cam Action Hook Design: this sliding window lock features with a cam action hook that holds the lock tight when locked; Install this kind of lock on the windows of your home can effectively prevent thieves from entering your home, and makes you live more comfortably,Sturdy Material: the window safety locks are made of quality zinc alloy materials, with exquisite workmanship, wearproof and stable, won't corrosion and rust easily, will serve you for a long time,Easy Operation: you firstly need to use a drill to make holes in your window, and then take the screwdriver provided with this product to fix the window locks on the window so that you can effortlessly install the vinyl window sash lock to protect the safety of the whole family