Mechanisms to safely secure astronauts to their seats in the Command Module were provided for all expected contingencies. When in their spacesuits, the boots were designed to strap directly into the couch footpan. If reentry were to occur with the astronauts wearing shirtsleeves or inflight coveralls a separate mechanism was provided each astronaut to secure feet and legs to the couch during the high G portions of reentry.
This is one of three sets of heel restraints stored in the Apollo 11 Command Module, "Columbia" during its historic mission. It was transferred to the Smithsonian along with the spacecraft's other contents in 1970.