DOUBLE SEGMENTS - diamond encrusted bar segments allow longevity and higher productivity SOFT BOND - suitable for grinding medium hard to hard concrete GRIT SIZE & SET - #30/40 grit size includes 3 grinding discs for Iron Horse, Warrior, XtremePolishing & ASL 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. Soft bond is ideal for medium to hard concrete. #30/40 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 grinders.