JJC QTS-4 Power Connection Cable for PENTAX AF-540 FGZ AF-500 FTZ Vivitar 3900 Flashes with Quantum Instruments Turbo Series Battery Pack as Quantum CN3

Cable functions correctly tested with Quantum Turbo Battery and Pentax AF-500GTZ flash. Combination of cable and QTB lowers flash recharge time to 2 seconds for a maximum energy flash. Cable appears well made. Kudos to manufacturer for making this capability available. Pentax's off-flash battery packs seem to no longer be available in the USA.Voltage caution: The Quantum Turbo Battery line makes use of a DIN connector to supply 330 Vdc to the flash unit. DIN connectors were developed for low voltage audio uses. The highest rated voltage for a fully populated pin layout DIN connector that I can find is 250V. Quantum may have been able to have their cables approved for higher voltage because they have removed the unused pins close to the HV pins. In the QTS-4, the pins are snipped rather than missing entirely. In very humid or very high altitude conditions, arc tracking along the pin mounting surface via the snipped pins might occur sooner for the QTS-4 than the no longer available CN3 Quantum cable and should be checked for if suspected.

This is an ABSOLUTE buy if you want to power your AF series flashes with a power pack. I should have bought two when I purchased it. I will be ordering more!