This wagon was a one-off vehicle and was built by the Railway Company in 1918 re-using the underframe of cattle van K.15; it was one of the last of the series to remain in regular use; this example was scrapped in 1960 and was built to the same pattern as others of the series which ultimately totalled forty-six as detailed elsewhere.

The use of this series dwindled latterly and the “M” series of drop-side wagons were favoured for their versatility, making this something of an oddity being created as late as 1918.  Despite this, Metropolitan furnished the railway with fresh drawings as late as 1925 for more of the type, the offer was not taken up.  H.46 was fitted with a handbrake, as were other members of the series, albeit retrospectively.