DOUBLE SEGMENTS - diamond encrusted bar segments allow longevity and higher productivity MEDIUM BOND - suitable for medium soft to medium concrete GRIT SIZE & SET - #18/20 grit size includes 3 grinding discs for ASL, Iron Horse, Warrior or XtremePolishing planetary grinders NON-THREADED HOLES - 3 x 8.5mm non screw holes designed for grinding machines with 3 non threaded holes for the RTS Iron Horse Grinders USE WET OR DRY - walkbehind grinder recommended Trapezoidal diamond grinding tooling with 3 x 8.5 mm non-screw holes designed for floor grinding machines with three non-threaded holes, including variants with magnetic plates. Medium bond is ideal for medium-soft to medium concrete. #18/20 grit, comes in a set of 3 pieces. Use wet or dry with Iron Horse Planetary grinders such as RTS /750-T9/650-T8/600-T1/550-T7/500-T2/T3/460-T6 or Warrior, XtremePolishing & ASL floor grinders.