The Rolex Oyster Perpetual Day-Date is a COSC certified, self-winding chronometer manufactured by Rolex. Initially presented in 1956, the Day-Date was the first watch to display the date, as well as the day, in its entirety. The Day-Date is one of Rolex's watches that is made only in solid 18k yellow gold, 18k white gold, 18k everose gold (Rolex's version of 18k rose gold) and platinum (PT950). Additionally Rolex manufactures a specific bracelet only available for the Day-Date line, the President bracelet. Due to the name of this bracelet, the Rolex Oyster Perpetual Day-Date is commonly referred to as "Rolex president" or "presidential Rolex".