The World Administrative Radio Conference (WARC) bands are three portions of the shortwave radio spectrum used by licensed and/or certified amateur radio operators. They consist of 30 meters (10.1–10.15 MHz), 17 meters (18.068–18.168 MHz), and 12 meters (24.89–24.99 MHz). They were named after the World Administrative Radio Conference, which in 1979 created a worldwide allocation of these bands for amateur use. The bands were opened for use in the early 1980s. Due to their relatively small bandwidth of 100 kHz or less, there is a gentlemen's agreement that the WARC bands may not be used for general contesting. This agreement has been codified in official recommendations, such as the IARU Region 1 HF Manager's Handbook, which states: "Contest activity shall not take place on the 5, 10, 18, and 24 MHz bands."