Power Grip.
A power grip requires firm control and gives greater flexor asymmetry to the hand. During power grip, the ulnar side of the hand works with the radial side to give stronger stability. The ulnar digits tend to work together to provide support and static control. This grip is used whenever strength or force is the primary consideration.
Precision or Prehension Grip.
The precision grip is an activity limited mainly to the metacarpophalangeal joints and involves primarily the radial side of the hand. This grip is used whenever accuracy and precision
are required. The radial digits (index and long fingers) provide control by working in concert with the thumb to form a “dynamic tripod” for precision handling.