... Metal bondROUGH & MEDIUM 50#60#70#80#120#200#BPerformanceis better than Magnesia bond, Long lifespan , high efficiency, savingelectricity, few ... type, long lifespan, good at safety, common use.Frankfurt Abrasive CompoundFINE 400#600#800#1200#DPerformance is better than normal type, high ... #2000 #3000#6000#10000#HCan instead of CLEANER , good at safety and high efficiency. (6000#is common use).