Proposal to clarify that Child Restraint Systems approved according to UN R129 or R44 may be used in vehicles of categories M₂ and M₃ with a 3-point belt and/or ISOFIX attachments without further requirements. As a result, Part I of UN R170 covers Built-in Child Restraint Systems for securing children from 40 – 150 cm in forward facing and rearward facing vehicle seats and Part II addresses Child Restraint Systems approved according to UN R129 or R44 which may be installed in a bus seat with a 2-point belt.