A hit and miss product
These coils are needed to make the Halo Triton function. That written, some times they work, some times they don't. I recently bought a five pack of coils only to discover that three of them failed to engage the battery. I know this because I tried the new ones in the different batteries I own and each time the light on the battery's side flashed; indicating that the coil unit was not working with the battery (I left the liquid sit in the mini tanks for more than an hour so the liquid would absorb into the wick, but with no success). I changed them out with the old coils that I had been using and all the battery's worked fine. These coils are necessary evils. Be sure to stock up on the coils just in case some of them do not work.