The RENFE Series 596 railcars were re-built from the 2-unit railcars of the 593 series by attaching the cabin from the trailer to the other end of the motorized unit. The reconstruction work was carried out at the MIT (Maintenance and Industrial Workshop) in Valladolid, where a new cab was installed at the cab-less end, a more comfortable and spacious interior was fitted, and the diesel engine transmission and control system was improved. The first six units retained the original bodywork, but the rest of the series received fairings that gave them a more modern appearance. These models come in various liveries and with different running numbers, allowing different units to be coupled in double-traction thanks to their fully functional “Scharfenberg” coupler. The driving cabs have been detailed with the original control console of these railcars, and the end lights are reversible, featuring a main headlight and two lower white lights, as well as upper red marker lights and a lower red tail light. The bodywork includes numerous details such as grilles, different inspection panels, and rearview mirrors. It also features a circuit board with a 21-pin NEM 660 socket and space for a speaker in sound decoders.