The heavy duty Extech HD400 / HD450 light meter features a rugged design with an easy-to-read, large backlit display. The handheld Extech HD400 / HD450 light meter, weighing only 13.7 oz., has a wide range up to 40,000Fc (400,000Lux). The HD450 model also includes a data logging function, with the ability to automatically store up to 16,000 readings or manually accept/recall 99 readings.

The Extech HD400 / HD450 light meter utilizes a precision silicon photo diode and spectral response filter. A peak mode of 10µS allows the Extech HD400 / HD450 light meter to capture the highest reading. Other functions included are a min/max and data hold. The Extech HD400 / HD450 light meter also features a USB port allowing you to easily connect directly to your computer.