1The pump cover can be screwed by hand to quickly disassemble and convenient to tube replacement. 2The adjustment roller is used for adjustment, which is convenient for the user to replace the tube, so as to avoid pinching and destroying the tube due to lack of experience of the user. 3The roller bearing adopts a wheel frame, which is silent and has a long service life. 4Stainless steel screws, good corrosion resistance. 5The motor of the pump is a stepper motor with high control accuracy, low power consumption and stable performance.Feature: The pump cover can be screwed by hand to quickly disassemble and convenient to tube replacement.The adjustment roller is used for adjustment, which is convenient for the user to replace the tube, so as to avoid pinching and destroying the tube due to lack of experience of the user.The roller bearing adopts a wheel frame, which is silent and has a long service life.Stainless steel screws, good corrosion resistance.The motor of the pump is a stepper motor with high control accuracy, low power consumption and stable performance. Specification: Working voltage: 6~30V Working environment: 0-40, relative humidity 80% Flow direction: the flow direction of the pump depends on the positive and negative connection Flow range: 0 - 400ml / min Tube: inner diameter x outer diameter (6.4mm x 9.6mm) Wall thickness: 1.6mm Maximum diameter: 9.6mm Tube material: transparent silicone tube Shell material: PC Roller: 304 stainless steel wheel frame Roller type: ball bearing Package list: 1 x Pump 1 x Hex Wrench Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product. Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.