Square D PK5GTA Qo Ground Bar Assembly Brand: Square D. Part Number: PK5GTA. Square D QO Ground Bar Assembly, Surface Mount, 2-1/4 in Length, Aluminum/Copper Conductor, 5 Terminals, 14 to 4 AWG Conductor, For Use with: QO Load Center. Additional Description: SQD -PK5GTA LOAD CENTER EQUIPMENT GROUND BAR ASSY. Catalog Description: Load center accessory, QO/Homeline, ground bar kit, 5 terminals..