All cam arms sold here are either original equiptment in the Comet drive clutches or a popular replacement for trail riding or racingCam arms will not always be stamped with the name they are called because they are often made from another cam armNote: All carm arms are sold EACH - You must order FOUR of these arms to get the correct cam arm weight for a 4-Pro clutch and THREE for the 102-C, 108-C, and 108-EXP cluthesNote: Comet arm weight objective is within .75 grams of that listed. Certified weights would be significantly more expensive. The variance may occasionally exceed 2 grams and is a result of greater or lesser arm density