Unified Thread Gauges are manufactured in accordance with both British and American standards. The British Standard follows basic dimension specifications as per B.S. 1580-1962 and gauging practice as per B.S. 919 Part 1/1960. For the American Standard, basic dimensions follow ANSI/ASME B1.1-1982, and gauging practice is based on ANSI/ASME B1.1-1983. The class of fit is defined as 2B (Medium) for plugs and 2A (Medium) for rings. The range includes No. 0x80 TPI to 10 TPI.