|  | 5.4 | Layer 1 Components and Devices
| 5.4.4 | Jacks
RJ-45 plugs fit into RJ-45 jacks or receptacles. The RJ-45 jack has eight conductors , which snap together with the RJ-45 plug. On the other side of the RJ-45 jack is a punch down block where wires are separated out and forced into slots with a fork-like tool called a punch-down tool. This provides a copper-conducting path for the bits. The RJ-45 jack is a Layer 1 component.