Essential Tools for Energy Saving Consultants Designed for professionals who audit existing and replacement lighting systems for energy efficiency and lighting performance, this Extech Lighting Retrofit Kit is ideal for auditing the performance of existing lighting systems, as well as verifying lighting system output after installations and retrofits. The kit features three compact tools that are indispensable at various locations: the easy-to-use LT300 light meter that measures up to 20,000 ft. candles/200,000 lux, the DT300 laser distance meter with built-in tools to quickly calculate area, even in hard-to measure locations, and the 380940 400 amp AC/DC clamp meter a versatile electrical test tool with built-in wattage measurement.