There were two versions of it, a 1.00 and a 1.25, one cu. in. and 1.25 cu. in respectively. The 1.25 will turn a 15x8 in the 7,000 to 7,200 rpm range, I've never had 1.00. It has a needle bearing rod. John Maloney did all the testing on the prototype 1.25 with the 15x8 and it is the only recommended prop. It was made in Korea. The carb is too big but it runs OK. Once started it will run quite reliably and is very frugal on gas.