DIOXIT Window Lock and Window Screen Lock Safety Sliding Window Frame Stopper-4PCS Child Safety Strap Lock  (Silver)

"It is strong,solid and sturdy, exquisite workmanship, aluminum alloy frame that can be reused many times. There is no need to install extra tools,it is equipped with a hex key in each window locks, holding on the track by key control. It can be easily applied to most environments; By keeping the windows partially open and closed. It is burglar-proof and can prevent children from falling and protect the safety of their families while improving air circulation. Size : 3 x 2.5 cm ( W x H )"