Long coiled locking cable for Quantum QB1 (Plus) & QB1c (Compact) Batteries. Connection is made through battery compartment in flash. Supplies 6 volts from Quantum battery for select flashes such as Achiever, Braun, Canon, Cobra, Contax, Lumo Pro, Metz, Minolta, Olympus, Osram, Pentax, Phoenix, Ricoh, Soligor, Sunpak & Vivitar flashes.