First of all, make sure you aren't in too small diameter a tree. If it's too narrow, the teeth won't seat properly. Secondly, you can use the strap that you use to hold the top and bottom portions together to secure the seat to the tree. Watch the video that came with it, it explains it there. If all else fails, ratchet strap. I use a Viper and stability has never been an issue, unless the tree was too small.