This is a Mitutoyo 526-123, .4" - .7" X .0001", Split Ball Dial Bore Gage.
http://www.ebay.com/itm/Mitutoyo-526-123-4-7-X-0001-Split-Ball-Dial-Bore-Gage-/131881928274



Besides failing to go beyond .7" it can only measure 2.4" in depth.

Pete