Pyle PST30 Digital LED Non Contact Stroboscope Tachometer with Backlit LCD Display and 19999 RPM Range Large lcd display with backlight - greater than or equal to 1,000Rpm: coarse adjust: 100Rpm, fine adjust: 1Rpm Digital control to adjust flash frequency - accuracy: 0.05% Low power consumption - resolution: &lt;1,000Rpm: 0.1Rpm =1,000Rpm: 1Rpm Large LCD display with backlight - Greater than or equal to 1,000RPM: Coarse adjust: 100RPM, Fine adjust: 1RPM Digital control to adjust flash frequency - Accuracy: 0.05% Low power consumption - Resolution: &lt;1,000RPM: 0.1RPM =1,000RPM: 1RPM Range: 60 ~ 19,999RPM - 7.68in x 2.87in x 1.5in Less than 1,000RPM: Coarse adjust: 10RPM, Fine adjust: 0.1RPM - Battery: 4x1.5V AA battery