new GEC - http://cdn.kempstoncontrols.com/files/15efdd248e8c43c12e184853fd41345d/DPE100B40/030.pdf
old GEC - http://www.gepowercontrols.com/eu/resources/literature_library/catalogs/residential/downloads/DS_Catalogue_Consumer_units_and_MCBs_English_UK.pdf
Busbar looks similar..