The Triplett Model TNM50 Tint Meter measures the transmittance of light for use on automotive windows, insulation paper, organic material, painting, coating material, film, glass, and plastic sheet. It can also measure the sun blocking capabilities of window curtains. It has a 0 to 100% transmittance range with a 0 to 1/4" (0 to 6.5mm) thickness range and an accuracy of ±2%. It features a power-on self calibration. Readings are displayed on the 3-Digit, 999 count LCD. Automatic data hold locks the reading on the display for 30 seconds before auto-shutdown begins to conserve battery life. A continuous use function can be used to overide auto-shutdown for longer operating times. Includes Tint Meter receiver and transmitter, (2) standard transmittance sheets with plastic pocket, (2) CR2032 batteries, and carrying case. 1 year warranty.