What are floors B, G, R in the elevator?
when entering the elevator, on the control panel, besides the buttons 1, 2, 3, 4 ... corresponding to the position of the floors, we also see the appearance of symbols such as b,
Tags : elevator
The world's fastest elevator 'phi' with a speed of 1,260m / min
a 530m high lift built by japan's hitachi technology company at ctf financial center building in guangzhou, china has set a new speed record with the ability to move up to 1,260