Examples described herein include a backplane keying mechanism. The backplane keying mechanism may include a backplane, a first connector, a second connector, a first block for the first connector, and a second block for the second connector. The first block and the second block may be moveable as one unit on the backplane from a first state to a second state. In the first state, the first block allows the first connect to connect to a first type of device and the second block allows the second connector to connect to the first type of device. In the second state, the first block prohibits the first connector from connecting to the first type of device and the second block prohibits the second connector from connecting to the first type of device.