ES Shutter Fan Diameter:16" (3 Speed, 1200/2050/2950 CFM) GrowControl™ SXR Rain Sensor is

GrowControl™ SXR Rain Sensor is a high quality optical type rain sensor with no moving parts

If you are only going to keep your greenhouse plastic on for one year

and can withstand snow

Neoprene custom size cover

Some users simply need to monitor the temperature

ES Shutter Fan Diameter:16" (3 Speed, 1200/2050/2950 CFM) GrowControl™ SXR Rain Sensor isThe ES Shutter Fan is a durable agriculture grade exhaust fan perfect for barn and building peaks, greenhouses, warehouses, and more. ES Shutter Fans are available without a cord, or pre wired with a cord and plug for "No Electrician Required" installation. Fans ship fully assembled out of the box so you're up and running in no time! This exhaust fan is 115V, aluminum construction, and indoor outdoor. Available in 10, 12, 16, 20, 24 and 30 Comes fully