Power Con® is a new lockable power plug system (20 A, with permating earth contact) mostly used in professional audio & video systems, with measuring equipment, computers, lighting systems or for industrial use. The reliable contact & lock which prevents accidantal unplugging is enormously important. Two different non-conneting versions are available for short circuit protection. The blue A version for power in (provides unites with voltage from outside) & the grey B version for power out (delivers power to further connectable units, which means central voltage is available from one unite).