Draft UN Regulation establishing uniform provisions for type approval of electric powertrain retrofit systems (EPRS) for converting vehicles of categories M₁-M₃ and N₁-N₃ to full electric propulsion. Specifies approval procedures, application documentation, marking requirements, and technical specifications. Requires compliance with applicable UN Regulations including UN R10, UN R13, UN R100, and others depending on vehicle modifications. Defines roles of EPRS manufacturers and authorized installers. Includes transitional provisions for rechargeable energy storage system compliance: compliance with UN R100.03 required from entry into force to 31 August 2029, UN R100.05 from 1 September 2029. Covers conformity of production, modification and extension of approvals, and withdrawal procedures.