Locksimproved double glazing - Locks with double glazingDouble glazing can be used on heavy doors or windows to increase security.And it will be more sturdy, strong and sturdy, fine workmanship, aluminum alloy frame, stainless steel screws, can be reused.several times Lockdouble sliding window in quantityand in size with 4 keys;about 6 x 2.54 x 2.4cm/2.36 x 0.95 x 0.95inch (LWH), suitable for track height above1.2cm/0.47inch and track thickness not more than 1.6cm/0.63inch (not apply to middle track), please check your window rail;be before buying) Easy to useInstall - No need to install additional tools, each window lock has a key.hexagonal, which is fixed by the key control device.on the track.Designed for horizontal/vertical windows and sliding glass doors;not suitable for plastic window frames Wide range of uses - can be easily applied to any application.&àgrave;most environments;By keeping windows partially open and closed, anti-theft and anti-theft devices can prevent children from falling and protect the safety of your car.family members, while improving air circulation Product guarantee and customer service - we do not sell perfect images, but products;If you are not satisfied with our products, we will refund you for free or reship the new products for free.