Twenty VFKX flat wagons were modified in 1990/1991 to provide power to refrigerated containers loaded on them.
The Head End Power ( HEP ) supply was to be provided either by N class locomotives or a generator set built into a container.
The original VEKX number group was 200 to 219. During 1996 VQKX 1-9 were converted (not in order) to VEKX 220 to 228.
For a brief time during 2001/2002, VEKX 228 was recoded to VEKY.