A thin pad of heat resistant nomex felt fabric cushions each tile against the aluminum body of the Space Shuttle orbiter. Called a strain isolation pad, the fabric allows the vehicle to flex during the strain of liftoff, maneuvering, and reentry without cracking the hard tiles. The pads are glued directly to the orbiter on one side and the tiles on the other with a rust-colored silicone adhesive called RTV. This strain isolation pad, showing its glue, was removed from Columbia after its first flight in 1981. NASA gave a number of tiles and related materials to the Museum after that mission.
This object is on display in Human Spaceflight at the Steven F. Udvar-Hazy Center in Chantilly, VA.