Found: A Miniature Working Model of the National Archives Vault

AtlasObscura:

“To help illustrate the inner workings of his latest creation for the Archives, Ed Mosler Jr. pointed Nixon to a refrigerator-sized electric model. With the flick of a switch, they watched in dollhouse-scale as a tiny Constitution lowered from its display case and tucked into a subterranean armored strongbox. Lest anyone forget the master safe builder behind this unique device, the model helpfully bore the name “MOSLER,” in 72-point bold font.”