The Tramex Skipper 5, SMM5, is a dual-depth, non-destructive Marine moisture meter which safely detects excess moisture hidden in GRP boat hulls, decks and coach roofs including sandwich or cored structures. The unique three-electrode array provides both shallow (10 mm / ⅜") and deep (30 mm / 1¼") perceptivity to help establish the depth of any moisture within GRP composites.