The Welch 202701 Self Cleaning Vacuum Pump is a favorite for the savvy vacuum user. The self cleaning feature allows the pump to provide years of work horse duty, prior to servicing. The self cleaning feature also keeps the pump clean and dry, allowing the pump to immediately achieve deep pressures after use. The 202701 is an excellent rotary evaporator vacuum pump, but can be used for any harsh chemical duty service. At 2 Torr and 35 lit/min, this powerful pump strips DMF at 35C degrees. The pump is ergonomically friendly to control, with an anti-bumping switch and built in digital gauge.