Quality product, Comes with 2 pack, screws included for installation. Security: provide extra security for your windows against intruders，Keep babies and pets safe from sliding doors and windows; keep your toddlers far away from swimming pools, balconies, patios, etc. It is a kind of children's safety product, which can protect children from opening windows and climbing out without authorization. it can control the size of the window opening to prevent strong wind from blowing in, while also maintaining air circulation Easy to install: simple method easy to install using the screws provided size: 14 * 2.5cm, Manufacturer: Shun Yingtong