that's the seat belt type thing with a long strap that you wear going up and down the tree right? It's been a couple years. I have one of them and I tell you I wish I had 10. they work awesome. Any safety harness will work with it. you really feel safe climbing up to a portable with one of them. I got mine in the bargain cave at cabelas. they are pricey but WELL worth it. how much is your safety worth anyway?