DOUBLE SEGMENTS - diamond encrusted bar segments HARD BOND - suitable for grinding soft concrete GRIT SIZE & SET - #30/40 grit size includes 3 grinding discs USE WET OR DRY - walkbehind grinder recommended COMPATIBLE - fits Husqvarna PG 280/400/450/530/680/680RC/820/820RC Grinders Diamond grinding tooling designed for Husqvarna PG series floor grinding machines. 3 piece set with hard bond which is ideal for soft concrete. #30/40 grit with 2 diamond segments, use wet or dry with Husqvarna floor grinders such as PG 280/400/450/530/540/680/820/830.