 (2009 edition has dropped from reference the R4-2 speed derestriction).The speed derestriction sign (//) had developed 'different meaning' over time at state and territory level, although its contract-meaning under "The United Nations Convention on Road Traffic, Signs & Signals" where the sign is catalogued "C,17a", is; "End of all local prohibitions imposed on moving vehicles" and has never changed.In the Northern Territory, they designated the end of speed restrictions.