Made of Alloy, practical and durable.
It can avoid direct contact between hands and pollutants in the air.
"Keys" are really very small. Yes, the seller indicated all right, the length of the hook is 7 cm. But at the same time the seller made photo collage, where this "key" looks in the hand very large and convenient to hold. In fact, a child's finger goes through the hole with difficulty, not to mention an adult hand. In short, the door will not open for them, it remains to use it only as a rear door, to press the elevator buttons. ((( The idea is good, but the performance pumped up...