Dewalt built 10-amp AC/DC 11,000 rpm motor designed for faster material removal and higher overload protection,Dust ejection system provides durability by ejecting damaging dust and debris particles that enter the tool through air intake vents,Low-profile jam-pot gear case provides precise gear alignment for a smoother, quieter transmission,The spindle dimension is 5/8 x 11 in. and it's One-piece brush arm prevents brush hang-up due to dust ingestion,Quick-change wheel release allows tool-free wheel removal without need for a wrench