Zhongyan 3 stage up to 4500psi is special design for airgun cylinder, stainless steel construction, cooled liquid filled can keep the hand pump in low temperature and the liquid will not be frozen even -20℃.
There is a better pump than 3 stage hand pump, that is 4 stage pump. The biggest different between 3 stage and 4 stage is the CONSTRUCTION. The 3 stage pump included total three tubes, but four tube the 4 stage have. It can makes the 4 stage pump up to 5000 or 5500 psi, and that will be more easy to fill a cylinder.
Usually, the max pressure of airgun cylinder can be held is 4500psi, but as a professional pcp pump manufacturer, we suggest 3000psi filled is enough for airgun cylinder. 4500psi is a very high pressure, if you fill 4500psi to cylinder every time, the lifetime of pcp pump will be shorten.
Know more details about the pcp pump, please just contact us by tongfy@hijinjiao.com or visit www.zypressure.com.