This roller chain idler sprocket unit guides and tensions chain drives through an integrated bearing supporting a sprocket wheel, made from steel or sintered iron. The bore diameter is 30.0 mm, outside diameter 62.0 mm, and net mass 1.09 kg, giving a compact unit combining the sprocket and rolling bearing in a single component. The sealed bearing arrangement built into the sprocket body simplifies mounting since the bearing and sprocket rotate together as one unit, removing the need for separate alignment between a shaft-mounted sprocket and its support bearing. This construction suits applications where a rotating idler point is needed within a chain drive layout, with the bore diameter of 30.0 mm defining the shaft fit and the outside diameter of 62.0 mm setting the sprocket engagement geometry.