The WC-8 has a special module that converts 12 Volts DC into a pulsed signal, that allows the unit to lift over 50 pounds to comply with DC specifications, but the pulsed DC field induces particle mobility similar to an AC Yoke. The WC-8 draws less than 1/2 Amp, so a 3.0 Amp/Hour Battery Pack will last you a full day (based on Western Instruments’ Battery Duration Tests). Western Instruments offers Battery Packs in 3.0, 7.0, and 12 Amp hour ratings (nominal), and all three can be charged with our High Capacity Smart Charger (1.5 Amps). We also offer our exclusive Dual Output Battery Pack, for use with our WC and W-8 Yokes, so a 12 Volt UV Lamp can be used for totally portable Wet Fluorescent Inspection.