From 1997  a number of former WGX type wagons were stripped of their bodies and converted to flat wagons to carry Nickel bins.  They were:

1997	WOAX 33115, 33135, 33206, 33211 to WFB WODX 33117, 33133, 33156, 33205 to WFB WOSF 33121, 33173, 33178, 33213, 33216 to WFB WOSX 33184 to WFB WOG 33119, 33127, 33158, 33169, 33201, 33209 to WFB/AFBF WOO 33166, 33180, 33194 to WFB
?	33063, 33069, 33076, 33121, 33137, 33162 to WFB

By June 2010 the WFB had been reclassified as AFBF flats and there were at least 28 of them (33063, 33069, 33076, 33115, 33117, 33119, 33121, 33127, 33133, 33135, 33137, 33156, 33158, 33162, 33166, 33169, 33173, 33178, 33180, 33184, 33194, 33201, 33205, 33206, 33209, 33211, 33213, 33216).