How to make hands always physical?

I have hand models that I want to always be physical colliders without having to hold down a button. My hands are a prefab with a mesh filter, renderer, and a bunch of collisions hulls as children so it can be a non kinematic concave collider. I've tried manually attaching the prefab to the hands but that doesn't work, neither does forcing the phyiscal hands to be enabled at runtime, which seems to always crash Unity.