Lifting heating bath-glass ware is fixed firmly, which decreases damage. \n\ncollecting 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.