This is the Backwoods Miniatures Class 5 kit with the Worsley Works kit to convert it to a 5A. The latter provides new footplate, valances, tanks and bunker which go together reasonably well although some of the tabs don't fit the slots and there is a gap below the front of the tanks. Matching it up with the original kit is more problematic, there is a poor fit between the cab/bunker/tanks, particularly in relation to height but this was overcome relatively easily. The 5A is 1'5" longer than the Class 5 so, as you don't get a replacement chassis, the original one needs lengthening. Unfortunately this involves two cuts not one, as you need to insert 4mm in front of the rear bogie and 1mm behind it. Nothing that can't be fixed with the soldering iron and some scrap etch!