[Precise accuracy] The scale is clear, the is automatic, and the dosage and fertilizer varieties can be changed at any time. [Uniform dissolution]-The device moves up and down in the cylinder, and when the water is pressed out, the additives at the bottom of the container are evenly sucked into the water through the pipe. [Easy to install] that the inlet and outlet of the proportional pump are in the same direction as the water , and the proportional pump is sealed. If additives are to be added, the valves on both sides of the pump can be opened proportionally. [Wide application]-Suitable for occasions where liquid is required, such as animal husbandry, industrial dilution, brewery, agriculture, industrial washing, sanitation, etc. Note: 1- When using an automatic proportional pump, make that the container containing the liquid additive is not empty 2-Air release valve: At the beginning of starting the proportional pump, the air release valve should be pressed down for a few seconds to exhaust the existing air inside, and the air release valve should be closed quickly. 3- During installation and use, that the water inlet end of the proportional pump must be equipped with filtering equipment. 4- If the working resistance increases during use, lubricating oil should be added to the to increase the service life. 5- After use, clean the proportional pump with clean water to reduce corrosion and extend the service life of the proportional pump. Precautions for product use Proportion range: 0.2%-2% range: 12L/H-3000L/H Working water pressure: 0.2-6 kg Inlet and outlet diameter: 32mm / 25mm color:Blue Material:plastic size:About 38 x 17cm Package Contents: 1 x Proportional Pump (with accessories) Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.