Belt drive vacuum pumps are the right choice for laboratories working with corrosive vapors (such as extraction labs).
Typical features for belt-drive pumps include corrosion-resistant construction, low RPM operation, fewer moving parts, and large oil reservoirs. The unified result is a vacuum pump that's resistant to corrosive vapors and durable even after years of heavy use.
Welch is a premier American manufacturer of belt-drive vacuum pumps. Their ChemStar and DuoSeal series are productive fixtures in hundreds of laboratories.