I have one and i am not that impressed with them but they are china made and cheap.Not being a bubble buster but the koyo's are better made and the 510 one they make is a very close fit. And they were no help for me when i went to there main office in Irvine,they never let me in the building and it was 102 degrees outside,no class.I found a new company that looks like will make me happy but it will cost twice if not more as much but quality stuff.