This single-row cylindrical roller bearing (NJ306-E-XL-M1-C3) has a bore of 30.0 mm, outside diameter of 72.0 mm, and width of 19.0 mm, with a net mass of 0.415 kg. The outer ring carries two ribs and the inner ring one rib, forming a semi-locating bearing configuration of type NJ. The cage is machined brass, designation M1, and the E design provides an optimized internal geometry for increased load carrying capacity. Limiting speed is rated at 18500 1/min, with a reference speed of 8900 1/min. The radial internal clearance falls in group C3, allowing for tighter fits and compensation for thermal expansion during operation. Since this is a semi-locating design, the bearing accommodates axial displacement of the free ring relative to the ribbed ring, making it suitable where one bearing position must handle axial loads while the other allows for shaft length variation due to temperature changes. The open design without seals requires external lubrication and housing protection, and the roller-rib contact geometry supports predominantly radial loads with limited axial guidance from the single rib on the inner ring.