24-Hour Fan-Aspirated Radiation Shield - SKU 6838A motor driven fan draws a constant airflow through the sensor chamber at 500 feet per minute (2,5 m s). At night, when the effects of radiation are less, this solar powered model runs on battery power and the airflow slows to 280 feet per minute (1,4 m s). Install your own sensor in the sensor chamber. Sensor chamber: 2. 24 x 3 (56,8 mm x 76,2 mm). Includes 10 plates, rechargeable batteries, mounting hardware, and 25 ft. (7,6 m) cable. Highlights