0.3 HP Motor Output - more powerful than pneumatic 0.25HP die grinders Max RPM = 24,500 1/4" Collet, 1/8" compatible(sold separately) Optimized RPM setting for most common accessories Dial in the right Max RPM for safer operation Mode 1 = 10,000 Mode 2 = 15,000 Mode 3 = 20,000 Mode 4 = 24,500 No air hoses, compressors or daily maintenance Replaces compressors and air hoses Increased cost savings over pneumatic power Compact tool size allows access in tight spaces