International Watch Co., also known as IWC, is a luxury Swiss watch manufacturer in Schaffhausen, Switzerland founded by American watchmaker Florentine Ariosto Jones in 1868. They are the only watch manufacturer based in East Swizerland. IWC launched the AquaTimer in the 1960s as a response to the increased popularity of diving as a sport. It features a rotating bezel protected under the crystal to prevent accidental changes and the case is water resistant to a depth of 1000 metres. The internal bezel is unidirectional and controlled by the bottom crown.