Power Tools for Professionals



Two-Speed Hammer Drill

The Bosch HD21-2 Two-Speed Hammer Drill features outstanding power, with a 9.2 Amp motor that handles all masonry drilling applications. This hammer drill features a maximum of 51,000 BPM for productivity in concrete and masonry. The dual-mode selector easily converts from rotation-only to hammer-drill mode. Its rotating brush plate allows users to back out bound-up bits. It has two speed settings, one for high speed and one for high power. It has a 360° torque-control auxiliary handle that securely locks into place for great control in heavy-duty drilling operations. The handle has a built In. depth gauge for accuracy. This robust drill has a metal front housing for longer life, a heavy-duty keyed chuck for performance and an overload clutch for security against recoil.

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  • (1) HD21-2 Two-Speed Hammer Drill
  • (1) 360° Auxiliary Handle
  • (1) Depth Gauge
  • (1) Chuck Key
  • (1) Carrying Case


  • Powerful 9.2 Amp motor – for high-torque and high-speed drilling capabilities
  • Auxiliary handle with built-in depth gauge – securely locks into place and provides consistent drilling depth
  • Integral slip clutch – more user security because it disengages the output shaft should the bit get into a bind situation
  • Rotating brush plate – delivers extended brush life and provides equal power in forward and reverse
  • Securely clamping, 1/2 In. three-jaw chuck — for rugged hammer-drilling applications
  • Dual-mode selector – easily converts from rotation-only to hammer-drill mode
  • Pistol-grip handle – includes a compact ergonomic design with soft-grip
  • Variable-speed reversing trigger — for accurate bit starting, as well as removing fasteners or bound bits
  • Metal gear housing — for long life and rugged jobsite durability
  • Two speeds – high speed for concrete, high torque for drilling in wood and metal
  • Works with Bosch PRO+GUARD™ dust solutions – an end-to-end dust-collection system that helps users move toward OSHA Silica Table 1 dust compliance

Technical Data

Amperage 9.2
Chuck Design Keyed
Chuck Size 1/2 in
Height 9.0"
Length 13.5"
Max. Capacity in Concrete 7/8"
Max. Capacity in Wood 1-5/8"
No Load BPM 0-15,300 / 0-51,000
No Load RPM 0-900 / 0-3,000
Rating 120 V
Voltage 120V
Weight 5.9lb
Width 3.0"
Works With Dust Extraction/Collection Hood
Includes (1) HD21-2 Two-Speed Hammer Drill, (1) 360° Auxiliary Handle, (1) Depth Gauge, (1) Chuck Key, (1) Carrying Case
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Owner's Manual


Accessories and Attachments For HD21-2

BlueGranite Turbo™ Carbide Hammer Drill Bit Sets
BlueGranite Turbo™ Carbide Hammer Drill Bits
Daredevil® Multipurpose Drill Bit Set
Daredevil® Multipurpose Drill Bits
Flat Shank Drill Bit Set
Flat Shank Hex Accessories
Flat Shank Hex Masonry Drill Bits
Glass and Tile Bit Sets
Glass and Tile Bits


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