DESC: Unibody Powertrain - keeps gearing in alignment for the most durable drive train on the market Seel Reinforced Collar - Provides enhanced durability when dropped on the chuck Durashield Housing - Constructed to withstand real world conditions. Withstands repeated 1-story drops when the competition fails Hammer On/Ooff Ring - Easily turns hammer on and off wihtout changing the clutch setting easily Accessible Brushes - Quick maintenenance to minimize downtime, Manufacturer: Bosch