Their multi-packs are not such a bargain. They state that they do not offer any warranty on the Multi-Pack products since the price per unit is so much less than buying a single battery or atomizer. I recently bought a 5 pack of attys and a 5 pack of batteries. I received them 5 days ago. I didn't worry that they didn't offer a warranty, because I probably wouldn't bother returning an atty or a battery if it wore out just shy of the 28 day guarantee they offer on a single anyway
I didn't expect there would be any problem. So far I have one bad atty (done in 1 day) and three bad batteries.

I haven't opened or tried all of the parts yet. So much for the cute little devil. I won't be ordering parts from them again. I somehow thought that they had higher quality, but apparently not. The attys and batteries from my starter kits (from another vendor) are still going strong. I was looking for spares. I also liked the cute little devil. LOL. To add insult to injury they had a big sale the day after I placed my order, so I paid 20% more for my broken parts. Ah well
live and learn.