World Extreme Cagefighting (WEC) was an American mixed martial arts (MMA) promotion founded in 2001. It was purchased by Zuffa, LLC, the parent company of the Ultimate Fighting Championship (UFC), in 2006. In its final incarnation, it was made up of 3 weight classes: 135 lb (61 kg), 145 lb (66 kg) and 155 lb (70 kg). To accommodate the smaller fighters, WEC's cage was 25 feet (7.6 m) in diameter—5 feet (1.5 m) smaller than the standard UFC cage. The smaller cage is now used by UFC for selected events.