Description Are you looking for a professional, yet affordable exhaust fan? Are you in search of a sturdy, trustworthy tool that can do multiple jobs at once? If yes, look no further! Our professional exhaust fan must meet you needs. It is one of the best choices for you. Features - Color: black.- Material: plastic- Size: 8 x 8 x 1.5cm.- Rotating shaft form : no brush with oil- install hole diameter : 4mm- Lifespan : 20000h- Voltage : 5V- Power : 0.75W- The critical air velocity : 0.8cmm- Rotated :1800R/M- Made of plastic material, durable and easy to use, long service life.- Ultra-thin 15mm, strengthen the ventilation in the cylinder, increase the carbon dioxide content in the cylinder, promote the growth of plants.- Promote photosynthesis and accelerate plant growth.- Strengthen ventilation, let the plant breathe freely.- Low working noise, life as long as 20,000 hours.Package List1 x exhaust fan The critical air velocity