After 30 years of shooting spring piston airguns I decided to try the PCP side. I've been using this pump for a few weeks now. I've filled my Hatsan Flashpup 12 or 15 times and the pump has never let me down. I didn't have instructions but assembly was easy and there are many youtube videos to help you understand how it works. The only issue I had was that the plug that came with it (to check for pressure leaks) didn't fit the outlet. Make sure you have some silicone oil with you, although mine was a little oiled when it arrived. It would probably be a good idea to order additional filter media and/or an optional in-line filter to keep moisture out of your PCP. Seems like cheap insurance to keep your gun working properly.