"Classic Merlin" was from 1983 to 1990, agreed to many include the classic Merlin 206 (2 lines, 6 extensions), Merlin 410 (4 lines, 10 extensions), the 820, (8 lines and 20 extensions), the Merlin 1030 and 1070 having up to ten lines and up to 30 and 70 extensions respectively. Merlin Plus began it's life arpox 1987, and the Merlin II was seperate