D'Addario Slide Bar (Hardened Glass) - New, Unused - MEDIUM SIZE Glass Slide Bar * Glass Slide (PWGS-S, PWGS-M, PWGS-L): Made of hardened glass (borosilicate glass), featuring a smooth playing feel and durability. The edges are smoothed by heat treatment, and the 4mm thickness produces a warm and thick tone. Dimensions: Length: 51mm Outer Diameter: 28.5mm Inner Diameter: 21mm Weight: 34.5g *Please consider these as approximate measurements, as they are taken by an amateur. Thank you very much for viewing. We kindly ask for your consideration in purchasing.