USB8SR (fitted with eight 1A, high sensitivity signal relays and fixed screw terminal blocks

 

USB4PR2 (fitted with four 10A power relays & 2 part (male/female) terminal blocks)

 

USB4PR (Four 10A power relays, fixed screw terminal connectors & perspex cover)

USB8PR2 (Eight 10A power relays and 2 part (male/female) screw terminal connectors)