McDivitt's Apollo 9 Suit

The museum displayed a suit used by Jim McDivitt on the Apollo 9 mission.

As mission commander, McDivitt wore the version of the A7L suit which had two sets of chest connectors (so that he could be connected to the Lunar Module's environmental control system and until he donned his Portable Life Support System (PLSS) and switched to that.

I have a number of resources regarding the Apollo spacesuit.