Laser pickup. With 5-digit LCD display, measuring range from 2.5 to 99.999 rpm, accuracy: +/- 0.05% + 1RPM. Measurement distance from 50 to 250 mm. Two 350 mm long reflective test strips are included. Stores the min. rotation speed, the max. rotation speed and the last measured value. Operates with 4 pcs. 1.5V AA batteries.