About 9 out of 10 of the rebounders I've tested right out of the box all smell like formaldehyde. That new car scent combined with walking into a tire store. When I call them and they say its normal and it will fade off in a few weeks. Yea right!.
This smell lasts for at least 2 months and stays dormant in my home and when it gets hot or I put it in a hot car, the smell comes back again. There are only 2 rebounders that have no off gassing or any type of chemical leaching. These do not have rubber feet or plastic frames.
If I want no smell at all, I avoid rebounder spring covers made of Vinyl. Cheap vinyl is what gives that new car scent but so many toxic people actually like that smell... Ohhhhh.. that new car smell..
Look for a thick Naugahyde Cover. This is the material that professinal boxing gloves are made of. Not vinyl. The protective cover on the latest Cellerciser model uses Naughahyde. The Needak uses a Nylon cover. Its optional though. You can
For the extreme chemical sensitive people, even the nylon stitching can leach an offensive smell. The Cellerciser has no scent of all. It also uses polyester stitching around the mat to connect the springs instead of nylon that has the odor off gas.
Rubber feet are what give the tire store smell. Cellerciser also uses polymer for their feet material instead of rubber.
Another thing I like about the latest Cellerciser is that it's Anti-Static. Some rebounders generate static.
The New Zealand Lymphaciser and the Cellerciser are my top two picks for someone who is sensitive to chemical off-gassing.