For sale is a used 1 groove B belt pulley. The hub has a 2-3/4" offset and the bore is tapered, 1" dia. on the big end and 7/8" dia. on the small end. The hub bore is 1" long. There is no set screw or keyway. The pulley was held in place with a shaft nut and the flat spot in the hub kept it from spinning on the shaft. If you have any questions, just ask.