The Bower 48220D is a double-cup, tapered roller bearing (double-cup design) cataloged as a tapered double outer (TDO) variant in Timken/Bower references. It uses two cups to form the race set and has an outside diameter of 182.563 mm (7.1875 in), a cup width of 73.025 mm (2.875 in), and a bearing width of 85.728 mm (3.375 in). Source Atlantic lists it as "Bower Cup" with these dimensions and notes compatibility with J Series Four Row Medium Tapered Roller Bearings. Timken’s CAD listings place the 48220D within the NA48290SW/48220D family, confirming its double-outer (TDO) design and bearing arrangement.
