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Koki Holdings Co.,Ltd.


45mm (1-3/4") Rotary Hammers

AC Brushless Motor Rotary Hammer Series for drilling larger holes
Rotary Hammer DH45ME/DH45MEY
  • AC Brushless Motor
  • User Vibration Protection
    Only for DH45MEY
  • Alminium Housing Body
  • SDS-max Shank
  • iF product design award
AC Brushless Motor
  • Maintenance-free
The product life cycle is significantly extended by eliminating troubles with armature burnout, layer short and commutator wear. Besides, no carbon brush replacement is required.

AC Brushless Motor

  • Fastest drilling speed and highest demolition performance in its class even at voltage drop
The efficient brushless motor offers higher drilling performance even with an extension cord used.
  • Compatible with engine generators
Designed to be powered by engine generators as well, thanks to Our original compact and high efficiency inverter circuit.
Fastest drilling speed and highest demolition performance in its class
  • Fastest* drilling speed and highest* demolition performance in its class
The high efficiency brushless motor and the optimized hammering mechanism achieve the fastest drilling speed* and the highest demolition performance* in its class.

* As of March 2015. Among 45mm class rotary hammers made by leading power tool manufacturers, surveyed by Koki Holdings.
Reduced vibration and improved operating efficiency
  • Our original, pendulum dynamic vibration absorber (Only for DH45MEY)

reduces the vibration from concrete drilling or chiseling by moving a weight and a leaf spring in the opposite direction to the movement of the hammer.

Pendulum dynamic vibration absorber
  • Vibration-absorbing handle
provides high vibration-absorbing effect by employing both transatory and hinge units.
High durability
  • The internal double-insulation construction with a very sturdy aluminium die-cast body and a plastic internal stator holder
Alminium housing body makes the housing more rigid, significantly enhancing durability of the motor unit.
Improved handling
  • Control panel
Control panel 1. Push-button, constant speed control with variable speed
Due to the built-in electronic control circuit that can adjust the impact rate according to applications, four-step impact rates can be selected by the rotation speed selector switch.
Display Lamp
No Load Speed 110V
120/min 170/min 220/min 270/min
120/min 180/min 240/min 310/min
Full Load Impact Rate 110V
1,200/min 1,600/min 2,100/min 2,500/min
1,200/min 1,700/min 2,300/min 2,950/min
2. Power Lamp
lights up when the plug is inserted into an outlet.
  • One push action for quick bit mounting
One push action for quick bit mounting A bit can be mounted by simply inserting it into the tool holder.
  • Large change lever
Large change lever An up-sized mode change lever is located on the top of the tool body for easier handling.
  • Large trigger switch
Large trigger switch Upsized, easy-to-grip trigger switch for more control.
  • Continuous operation function (available for the Hammering Mode)
Continuous operation function keeps the tools running even after the trigger switch is released, making chiseling easier.


Model DH45ME DH45MEY
Capacity Drill bit: 45mm (1-3/4")
Core bit: 125mm (4-29/32")
Power Input 1,500W
Bit Shank SDS max
No Load Speed 110V, 120V, 127V: 120 - 270/min
220V, 230V, 240V: 120 - 310/min
Full Load Impact Rate 110V, 120V, 127V: 1,200 - 2,500/min
220V, 230V, 240V: 1,200 - 2,950/min
Overall Length 535mm (21-1/16")
Weight (including side-handle) 9.0kg (19.8lbs.) 9.5kg (20.9lbs.)
Vibration Total Values
(triax vector sum)*
Hammer drilling into concrete Vibration emission value : ah, HD = 13.5m/s2
Uncertainty K = 1.5 m/s2
Vibration emission value : ah, HD = 8.8m/s2
Uncertainty K = 1.5 m/s2
Equivalent chiselling value Vibration emission value : ah, CHeq = 14.2m/s2
Uncertainty K = 1.5m/s2
Vibration emission value : ah, CHeq = 9.2m/s2
Uncertainty K = 1.5m/s2
Standard Accessories Side Handle, Stopper, Rotary Hammer Grease A, Carrying Case
*The tri-axial vibration values were measured according to EN60745-2-6.
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