Routers and so on belong to the hardware but still work in these layers~!
Bridges work on the Media Access Control (MAC) sublayer of the data link layer, and are used to transmit packets across multiple network segments using the same communication protocol
Routers work on the network layer
Hubs work on the physical layer as do interrupters
NICs work on the physical layer
Repeaters work on the OSI/RM layer 1 which is the physical layer
Repeaters work on the OSI/RM layer 1 which is the physical layer
The bridge is the first layer of the OSI/RM layer, which is the physical layer
The bridge works on the physical layer. RM Layer 1, the physical layer