This unique hand-held stroboscope was made possible by the development of high-power LEDs. The 30W Super-LED delivers bright flashes at adjustable rates from 1 Hz to 250 Hz, ideal for the motion rates encountered in lab situations. Features magnetic pads on back for attaching to vertical steel surfaces. Specifications: * Display modes: Frequency (Hz or RPM) * Frequency range: 1.0 - 250.0 Hz; 1 - 15,000 RPM * Frequency resolution: 0.1 Hz; 1 RPM * Frequency adjustment modes: + Frequency doubling (X2) + Frequency halving (÷2) + Incremental by 0.1 Hz/6 RPM (+, -) * Bulb power: 30 W LED * Dimensions: 18cm x 6cm x 4cm * Batteries: Four “AAA” (not included) * Battery life: 3 hours continuous use