The Definity TN circuit packs contain solid-state circuits mounted on printed wiring. All circuit packs are 8 in by 13 in. The following connectors are attached to one end of a circuit pack: 200-pin connector to a TN-labeled pack; 300-pin connector to a UN-labeled pack. Faceplates on the circuit packs are sized to fill the width of a slot. A color code on each faceplate identifies the circuit type.