Hello! Sorry for the English. But I have found that if any oil enters the ratchet the gear inside will stick and get wedged due to the internal design. I opened my ratchet and cleaned all of the oil to fix the problem. The pawl no longer sticks to the 90 tooth gear without oil inside it. The Phillips screws on the ratchet face are easy to strip… I replaced them with M2.5x8 Torx screws for disassembly in the future if oil enters the ratchet again. I do not use these ratchets for drain plugs for this reason. I have found Koken, KTC, and Tone function fine for that.