sentences:  Armstrong moved to London in the early 1970s where he developed a new line of electric instruments, amplifiers and effects boxes.The Dan Armstrong London instruments were made of solid Honduran mahogany with sliding low impedance pickups, available as a six string guitar, and short-scale and long-scale basses.Armstrong also marketed a line of tube guitar and bass amplifiers and effects boxes, the Blue Clipper, Yellow Humper, Red Ranger, Purple Peaker, Green Ringer and Orange Squeezer.