Harder dildo materials?

I would be very careful about using one of the hard dildo materials in a harness anally/for pegging. The giver doesn't have any sensory feedback about what the dildo is doing, and it would be very easy to injure the getter. I suspect that might be why Eden doesn't list any as being harness compatible.

That said, with a small O-ring you might be able to use something such as the Nubby Fat Head (Don Wands), Glass Probe (WHK), or Awesome Blossom (Doc Johnson) would probably work. Be careful!

A stiff silicone might be a better choice - if there are any.