STROBOSCOPE DT-900 Portable Strobe is designed for non-contact RPM measurements and inspecting moving parts by "freezing" or "slowing down" the action. The DT-900 requires only one hand to operate, yet delivers performance comparable to much larger and heavier "pistol-grip" type models. Features Easy to use with just one hand. The changeable NiMH battery powers the stroboscope 1-2,5 hours. "LOW BAT"appears in the display if the energy becomes less. NIST-Traceable calibration certificate & test report optionally available Resolution of 0.1 Flashes per minute. Universal Battery Charger is supplied on "-U", "-UT" and "-UP" versions for use anywhere Worldwide on 100-265 VAC Complete Kit The DT-900 is supplied as a complete kit including stroboscope, rechargeable battery pack, battery charger with exchangeable plugs, spare flash tube, operation manual, carrying case with foam insert and space for additional rechargeable battery