It's in very nice physical condition. You know what you are looking at... The plastic lens must have shrunk and from what I have read this is common for them to fall out. I would just carefully stick it back in with some clear silicone (I'm leaving this job for the purchaser). Replacement covers are cheap and also readily available.
The item "Starrett Dial Bore Gage Set" is in sale since Saturday, July 11, 2020. This item is in the category "Business & Industrial\CNC, Metalworking & Manufacturing\Metalworking Inspection & Measurement\Indicators". The seller is "dying2live333" and is located in Joliet, Illinois.
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