Proposal to amend UN R173 to enable application to vehicles equipped with an Automated Driving System and vehicles of category X. The Regulation applies to vehicles of categories M, N, O, L₂, L₄, L₅, L₆, L₇ and T₁ regarding safety-belt installation, and vehicles of categories M₁ and N₁ regarding child restraint systems. For vehicles of category X, a seating position with steering control placed in front may be designated suitable for Child Restraint System installation if passenger seating requirements are fulfilled. The Regulation does not apply to vehicles of category Y.