... closed heater, simple structure, convenient for cleaning.6. AC induction motor stepless speed regulating, brushless, no spark, long life; ... 7. The system's sealing is very good, high vacuum, high evaporation rate, high return rate;8. The glass instrument adopting GG ... . Once cooperation, forever friendship. Welcom to contact with Taikang High quality laboratory instrument RE-2000A Rotary Evaporator