This is my second purchase of the water purifier sterilization uv system. First time everything worked great until I tried to clean the crystal, it cracked and I ordered this as a replacement because you cannot buy the parts. This time the first ballast I put on didn't work. Went through a whole installation a second time, cracked another crystal. At least I had a second one to put in. Finally replaced the new ballast with the second in the package and it worked, but then it leaked and leaked. Finally got that to stop. The uv works good when it works. The first time I ordered it was a 20 cost for shipping, this time 70 dollars! I don't mind paying the extra for shipping but it was quite a shock. I will probably reorder so that if anything happens I can just change it out. The plumber that came out to put in a bypass in was another 1000 while I awaited delivery. It's a very reasonable system when it works. Have recommended to others because we all need to be able to drink our water here. Just be very careful tightening the top and bottom adjusting knobs.