In the mid-1960s, nightclubs and discothèques continued to grow in Europe and the United States. Specialized DJ equipment, such as Rudy Bozak's classic CMA-10-2DL mixer, began to appear on the market. In 1969, American club DJ Francis Grasso popularized beatmatching at New York's Sanctuary nightclub. Beatmatching is the technique of creating seamless transitions between records with matching beats, or tempos. Grasso also developed slip-cuing, the technique of holding a record still while the turntable is revolving underneath, releasing it at the desired moment to create a sudden transition from the previous record. (This technique had long been used in radio.)