Cast-iron adjustable swivel mounting bracket, branded “POWRARM” and made by the Garfield Engineering Co. of Wichita, Kansas (marked “Patented — Model MA”).It’s a wall/surface-mount pivot base: the flanged bottom plate (with two screw holes) bolts to a wall or fixture, the bell-shaped housing holds a ball-and-socket style swivel joint, and the knurled thumbscrew on the side locks the angle once adjusted. The clamp bracket on top (with two bolts) would have held an accessory Untested

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