the CLC headliner material appears to be the same material as the lock-together high density foam padding used on the floor in workout rooms, etc. Costco has this for about $10 per 6 2x2ft squares. the flooring material is a bit thinner, but if I had it to do over again I would have saved about $300 and used the flooring material. I was not impressed with the pre-cutting of the material by CLC. yes, there will be slight variations in the construction the shell from builder to builder, but even given that there was too much trimming and fitting required, given what we paid.