DISC MOWER 9544 Models Made From 1973 to 1980s and Then only MOWER 9539 Models From 1989 (Designed in 1973). #5 MODEL: 9539 BRITAINS GREEN DISC MOWER. #1 MODEL: 9544 BRITAINS DARK RED DISC MOWER. #2 MODEL: 9544 BRITAINS DARK RED DISC MOWER.