A high energy, modular power pack system for Qflash models X/X2/X2d/X4d/X5d-R with 200-400-600-800 Watt-Seconds of portable flash power. Leave your AC studio flash at home? the Qpaq-X flash system works for both location & candid photography. Connect one or two Qflash X 400 watt-second heads & shoot in Manual, Automatic, TTL, or Strobo mode! Qpaq-X has a removable battery that is user replaceable. Select from either small or large battery modules to fit the needs of your assignment, Then add or remove PXC modules to create a compact 200 watt-second pack or a two head, studio system up to 800 watt-seconds.