The Wairarapa railcars were designed as an answer to this problem. They were intended to operate along the length of the Incline and take over Wairarapa passenger services from regular carriage trains. Their body was built higher than an ordinary railcar, with a raised floor, to enable them to pass over the raised Fell centre rail on the Rimutaka Incline. In design, they resembled a bus, and unlike a usual single-unit railcar that has a driving compartment at each end, the Wairarapa railcars only had one driving end, necessitating that they be turned at the terminus of their journey.