Mueller Lot of 5 Black Iron Pipe 3/4" x 1/2" 90° Elbow Fittings 520-143BG Used - Good. Some surface rust and wear from storage. Cast iron, unfinished finish. 3/4 in male threads to 1/2 in female threads, 90° elbow, two outlets. Five-piece set, each fitting measures approximately 2.5 in long, 0.5 in high, 2 in wide, and weighs about 0.2 lbs. Model 520-143BG. Brand: of. Material: Cast Iron. Included: five units.