W&H Straight and contra angle handpieces color coding (English)
Red contra-angle handpieces operate faster than the drive speed. This means that the operating speed of the rotary instrument is higher than the motor speed. Blue straight and contra-angle handpieces transfer the motor speed 1 to 1 and green contra-angle handpieces operate slower than the motor speed. This means that the operating speed is lower than the drive speed.
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