I had one made by authentic hand made from The Ukraine & it was bad to expand & contract when using. I made notches in the tip to be able to remove it with a screw driver & asked him what size Orings he used & then replaced them with a better grade Oring & it worked fine as long as you oiled it about every shot which was way to aggravating for me so i ended up selling it to another member after doing some trading with Frank on here for a basstackle dual injector. As long as i'm making plastics it will be basstackle injectors for me.