A66/4L680 V-Belt; Width: 1/2"
Understanding the Part Number
A – The A stands for an “A” section v-belt. This is considered a “Classic” v-belt style that has a top width of ½ (0.5) inches and a thickness of 5/16 (0.312) inches.
66– 66 inches is the inside circumference of the belt. For A-section v-belts, the outside circumference is found by adding 2 inches to the inside length of the belt. So, the outside circumference of the A66 belt is 68 inches (66+2).