Laboratory vacuum pumps are classified into water circulation type, diaphragm type, piston type or rotary vane type vacuum pump according to different internal design principles. These vacuum pumps each have their own advantages and characteristics. For example, a rotary vane vacuum pump can achieve extremely high vacuum in a short period of time, and a water circulating vacuum pump is inexpensive to manufacture and inexpensive. Piston vacuum pumps are a type of laboratory vacuum pump that has emerged in recent years and is gradually being promoted. One or two sets of piston rod assemblies are arranged in the cylinder, and the reciprocating action principle is adopted to mix the gas into and out of the gas valve piece. The piston type vacuum pump relies on the piston rod to inhale and exhaust, so there is no need to connect the water source or add the vacuum pump oil. It is a kind of oil-free vacuum pump, and it can be plugged in when using. At the same time, since the piston parts are generally made of specially treated aluminum alloy materials, the diaphragm pumps made of materials such as nylon and PTFE are more durable and do not need to be replaced for long-term use. Based on the above design structure, the oil-free vacuum pump of the piston structure has maintenance-free, small size and quiet operation, so it is suitable for liquid extraction, sample filtration, use of equipment as a gas source, vacuum drying oven, and the like. Such as the medium waste liquid suction, vacuum filtration can choose R300 this model, the size of the machine is small, the weight is less than 4 kg, saving desktop space, low noise; R610 can be used with vacuum drying oven, using 2-stage piston Structure, pumping speed can reach a higher degree of vacuum, fully meet the needs of vacuum drying. Detailed product information is available on the website of Shanghai Lingde Instrument Co., Ltd. Usb Microscope,Digital Microscope Display Screen,Lcd Screen Digital Microscope,Digital Lcd Display Microscope NINGBO VANCO INSTRUMENT CO.,LTD , https://www.vancoscope.com