Blue anodized metal arm bearing produced by Air-Lock for the Apollo space suit, measuring 5.5″ in diameter and 1.75″ thick, engraved on the edge with part numbers, "A6L-1Z4042-01-0MED, SN-197, Assy 9058." In very good to fine condition, with general wear. This arm bearing has been authenticated by Bill Ayrey, company historian at ILC Dover, the manufacturer of the Apollo, Shuttle, and Space Station suits, and is accompanied by a letter of authenticity. This type of bearing was critical to allowing the arm rotation which permitted a much greater range of motion for the lunar walking astronauts, particularly when using tools or driving the lunar rover.
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