all kinds of gas cylinder production. China shopping website is filled with sales funnel.I as a Chinese manufacturer of very long on the market, and OEM production of gas reservoir development design for 7 years.Used by traders sold to all over the world. I go to Shanghai expo display products this year.Pump pump up continuously, continuously work number more than 2000, the sealing ring is not bad.I have a factory produces its own high-precision cylinder tube, applied in PCP pump.All cylinder precision tube is stainless steel material, will not rust. So the pump just need to replace the sealing ring, precision tube don't need to replace and maintain.Are sold in China of the pump, the customer has a reaction using 2-3 years also not bad.