lifting heating bath-glass ware is fixed firmly, which decreases damage. collecting bottle sinks in ice water, thus the second evaporation is decreased. vacuum metre - fixed type vacuum metre has good looking and clear digitals. ball mouth-collecting bottle is combined by grinded ball, they can be assembled or disassembled easily, the sealing is perfect. sealing for prolonged use in high temperature-it insures the anticorrosion and long life of moving sealing. the sealing system function is excellent. ptfe sleeve-there is a ptfe sleeve between standard mouth glass bodies, it reduces the"dead connecting"of grinded glass mouth. the instrument is easy to assemble, disassemble and clean. vertical condenser-flexible, three king of choice can be did, with a cold trap, it can be used to collect evaporation vapour that has lower boil point. rotary speed is displayed by digital metre -rotary speed is controlled in a wide range of 4-210rpm, displayed by digital metre. the displaying is obvious and easy to read. device for loosening the bottle-the mouth of rotary bottle is iso29 standard mouth. the bottle can be loosed easily by turning the screw of the device, which reduces destroying the glassware. it overcomes the difficulty of loosening the bottle in high temperature. intelligent control of the temperature-control is in a wide range of circumstance temperature-180℃, water and oil can be used in bathing, (only one of them can be used at a time), thus it can find more application. the wave change of temperature is merely ±0.2℃. evaporation is stable. material is not easy to be punched. the control is no spark, which comes the good safety. low noises design.