I’m very dubious of 3D printed stuff but these have had a lot of good reviews on road and track cars. I believe they are printed from something fancy and then heat treated. The honeycomb lets it absorb the vibrations and keep it in place, the previous blue Powerflex put far too much vibration through the floor.

They’ve made a really big difference and still hold the heavy exhaust really well, I’m impressed but will see how they last.
Dave!