In 1980/1981, flexi-van container wagons from the TVF | TVX | VQBY | VQBX group were rebuilt to standard container wagons and coded VQGX. The number group was 1 - 16.
The container turntables were removed and a skeletal structure applied to the underframe to support containers and twistlocks. This gave most of the wagons a 'humped' appearance.
Most of the wagons to be converted had been stored with bogies removed at Newport Workshops for about two years prior to conversion.
In 1994 for NRC traffic, the wagons were reclassed to RQZX.