This product is anemergency release lock. It is made of solid materials. It is safe and durable. It can serve you for a long time without being easily damaged. It is an excellent emergency release lock that can bring you more convenience, allowing you to have a more comfortable experience.Features-Color:As Shown-Material:Steel wire, metal-Size:5.50X5.50X4.00cm2.16X2.16X1.57in- This door lock allows manual opening of the garage door in the event of a power failure or other opener failure.- This garage door emergency release lock is universally compatible with most brands of garage door openers.- Made of die-cast construction, brushed steel wire and metal for durability.- Widely used in bank, hotel, store, school, home, mall, and etc.- Simple installation, easy to use for beginner or professional, allow you to use in an orderly and stable way.Packing list1 x quick release lock2 x keys