The South African Class Experimental 6 4-8-0 of 1906 is a South African steam locomotive from the pre-Union era in the Cape Colony.In 1906 the Cape Government Railways placed a single experimental 10th Class steam locomotive with a 4-8-0 Mastodon wheel arrangement in service on the Cape Eastern System. In 1912 when this locomotive was assimilated into the South African Railways it was renumbered and classified as Class Experimental 6.