Abstract: A tank gauging bob is adapted to be releasably attached to a measuring tape for measuring the contents of a storage compartment. The bob comprises a generally cylindrical vertical elongated body having a measuring tape receiving lug and an extended portion which overlaps the lower portion of the tape and the point of attachment of the bob to the tape. The body and extended portion possess graduations on their outer surface whereby when the tape is attached to the body, the graduations form a continious consecutive reading scale with the measuring tape.