This new scale uses a weighted formula to account for several different measured variables of the weight block and/or core as well as the coverstock. Our whole goal here is to give you a better, quicker understanding of each Roto Grip bowling ball.

GUTS: We look at items including the radius of gyration at a multitude of positions (most measure only three), the shape and direction of the RG planes of this particular shape, the differential, and more. Higher numbers equate to a more aggressive core or weight block shape which produces more total ball motion.

GRIT: We take into consideration the highly-complex chemistry involved in producing our cutting edge coverstocks. Oil displacement and pliability are two of the measureables here. The number here relates to the strength of the coverstock, and higher values will indicate more aggressive shell materials.

GRIME: This will be a letter indicating the amount of lane conditioner this ball is designed to handle. Heavy Oil (H), Medium-Heavy (MH), Medium (M), Medium-Light (ML), and Light (L) are your options here. Realize that you can adjust the surface or layout of any Roto Grip ball so that it works across a variety of lane conditions.