A tool for monitoring conditions within a subterranean well includes a first body segment, the first body segment being an elongated member with an axial protrusion having a reduced outer diameter. A second body segment is sized for mating with the first body segment. A metal specimen circumscribes the axial protrusion of the first body segment so that an outer diameter surface of the metal specimen defines an outer diameter of the tool. A connection assembly releasably secures the first body segment to the second body segment.