Compared to flexible shaft machines, micromotors have less torque, however, their higher speed results in a comparable rate of material removal with a lighter touch. The simple cord connection between the handpiece motor and control box is another key advantage. Unlike the "drag" and general restriction in movement that you have with a shaft and sheath, micromotors offer much greater freedom of movement with no vibration. HP4-917 Control Box is compact with switches on the front for On/Off Power, Forward or Reverse Rotation, and Manual or Foot Speed Control. Speed can be adjusted from low to full speed using the dial on the box or with the foot pedal. An Overload Protector Light is also featured that turns red and sounds a beeping alarm when the motor stalls. This is the same control unit.
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