Outdoor Purpose Net Radiometer is a double sided device and has black conical absorbers with an anti-stick weather resistant protective coating. The Net Radiometer is designed for routine measurement of net radiation which is the balance between incoming and outgoing radiation under outdoor conditions. The Net Radiometer is based on a thermopile sensor and can be directly connected to voltmeter or data logger with an mV input. The Outdoor Purpose Net Radiometer requires no fragile plastic domes which results in a virtually maintenance free design.