... structure of the narrow V-beltsWrapping cloth, top rubber, tensile body, bottom glueNarrow V-belt type two: one ... for the reference system (metric), the cut-off points SPZ, ... SPA, SPB, SPC four; another effective system (Imperial), type sub-9N, 15N, 25N three.Mark narrow V ... method: SPB2500GB × × × × or 15N1600GB × × × × Narrow V-belt