The P-51 is the larger version of the P-38 used by mess hall cooks to open the big trays and large cans of chow. Easier to use than the smaller P-38, the P-51 is a full 2" long, the added length affords more leverage and doesn't require as much thumb pressure to use. They are especially good for smaller or arthritic hands. Many prefer them over the P-38s because a P-51 will open cans much easier and faster and will last much longer than the P-38. Great for families or friends sending them to their guy's in Iraq & Afghanistan.