In the mid 1950's, the railways introduced some special containers. For the transport of these, the KC wagons were converted form cut down _IY_ open wagons. The number group was 87 - 106, 112 - 121.
The class was originally in service as _K__ and later recoded to KC, hence the unusual number group.
By the 1970's, these wagons were in dedicated traffic transporting tallow. Main traffic was Melbourne to Wodonga, site of a pet food factory (Uncle Ben's).
Three wagons were converted to KMC_ in 1963. With downturn in tallow traffic, the vehicles were removed from service by the mid 1980's.