This deal features all 5 the standard sized lead filled bopper billets. The two larger sizes are 1-5/8″ and 1-3/8″, these two are constructed for heavy duty applications. The 1-1/8″, 7/8″, and 3/4″ sizes are geared for finish work. These employ advantage of “weight forward” to improved accuracy, billet speed and thus less breakage. Copper Boppers have become the standard in modern knapping.