DB992568 was built by Metro-Cammell in 1953 to lot 2682, diagram 1/586, 715 being built being built to this diagram altogether. It has a 20 ton bottom-discharge ballast hopper for engineers' use, codenamed "catfish". Fitted with controlled doors, it has vacuum brakes and used by British Rail and now by QRS for ballasting work. It has "To be returned when empty to Penmaenmawr" (a stone ballast quarry) painted on the side.Withdrawn from BR service in October 1986, it arrived at Quainton in 1987.

If differs from the dogfish ballast wagon (DB983905), which is designed to drop ballast between the rails and on both sleeper ends. The catfish ballast wagon in contrast drops ballast between rails only. With our "dogfish" ballast wagon and "shark" brake van, we can now make up a complete permanent way train.