Proposal to allow, at the manufacturer’s request, extension of a type approval to special purpose vehicles of categories M₁, M₂, N₁ and N₂ regardless of their reference mass provided the manufacturer demonstrates that the vehicle in question is a special purpose vehicle. This aligns UN R83 with EU Directive 2007/46/EC where approvals of vehicles with a reference mass less than 2,610 kg can be extended to special purpose vehicles exceeding 2,840 kg (e.g., armored vehicles).