Thank you for viewing. This is an Air sheet cover from Nishikawa Sangyo. I'm not sure if it's for a box spring, but it's a sheet cover. Please consider after confirming the size. I've included a photo of the tag with the size information. No returns, please. I found this while decluttering. I took it out of the package, but I haven't used it. It had been stored for many years, so I washed it once for the purpose of listing it. There are no smokers or pets. I may change the shipping to Yuu Yuu Mercari.