ISO 4250-3:2011 sets out the designation, contours and dimensions for rims for narrow- and wide-base off-road tyres primarily intended for earth-moving machinery. All dimensions in ISO 4250-3:2011 are given in millimetres and are applicable to the side of the rim which is in contact with the tyre. Annex A gives details on sealing ring grooves and O-rings for earth-mover rims.