In April 1999, ITU-T adopted new higher resolutions of 300 ´ 600, 400 ´ 800, 600 ´ 600, 600 ´ 1200 and 1200 ´ 1200 pels/25.4 mm while 100 ´ 100 pels/25.4 mm was introduced a year earlier. This amendment assists the comprehension of the appropriate square resolution subset of these new resolutions: it is also written in a manner that accommodates future T.30 resolution enhancements without requiring corresponding amendments.