Applications & Features： 1.Small dimensions, low noise. 2.The big oil tank prevents the oil temperature from going up and delays the changing revolution of vacuum oil. 3.the oil lubrication system and the compressed inlet oil by the oil pump which are develop by the companys thchnical department has got the national patent(2XZ-8B). 4.It got the national patent and also the gold medal of the production exhibition in 1994(2XZ-8B).