Same here. I'm pretty sure nobody is going from small bolt to truck wheels anytime soon. I did ask them what the bolt patterns are and waiting on a reply.
they replied
This adapter is 5 on 4
Answer:
“This adapter is 5 on 4" bolt pattern holes and 5 on 5" bolt pattern studs for the wheels to bolt on. These have 1/2"-20 studs and the adapters are 15/16" thick.