This document establishes the load ratings of the diagonal code designated (ply rating marked series) tyres for agricultural tractors, trailers and machines. Tyre designation and dimensions, and approved rim contours are given in ISO 4251‑1. NOTE Code designated diagonal tyres (ply rating marked series) for construction applications (industrial tractors), identified by the classification code R-4, as specified in ISO 18805, or by suffix "IND" are part of ISO 13442. Code designated diagonal tyres (ply rating marked series) for forestry machines, identified by the classification code LS, as specified in ISO 18805, are covered by ISO 18807.