(This site is at a very early stage, so lots of missing stuff! See Joystick_Directory:About for more.)

Mastertronic Magnum

From Joystick Directory

Reviews

"As the name suggests, this joystick is gun-shaped, with the the fire button falling under the thumb and the shaft on top. It fits nicely in the hand and a prolonged playing stint produces no really bad side-effects on the hand." 8/10
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"..The Magnum is ideal for a whole host of games, ranging from arcade adventures to super fast shoot 'em ups."
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Sources