Things I liked:The tool is well made and works very well. The inlet valve seal did not work in my rifle a Model "C" (Racine) serial number 314XXX (1980). This was a disapointment as the main problem with the rifle was at the inlet seal. I used a modified faucet washer instead on the original brass support, worked perfectly. My lead seal was still OK so I can not comment on the use of the white pastic ring that is substituted in this kit but I have my doubts. Instructions are near worthless but Airgun Blog has perfect directions with photos. Things I would have changed:Needs to be available without the tool for the next rifle to be resealed. What others should know:This is not job for someone who has not been inside an airgun before. Job requires at least moderate skill and experience.