This needle roller cage assembly guides a single row of needle rollers within a JN cage, running at a width of 21.0 mm and a net mass of 0.124 kg. The limiting speed reaches 4750 1/min, while the reference speed is set at 3100 1/min, giving a clear margin between continuous operating conditions and the maximum permissible speed. As a cage-and-roller unit without integral inner or outer ring, it must run against a shaft and housing bore that serve as the raceways, which keeps radial section height low and allows the rollers to carry load directly against the mating surfaces. This design supports arrangements where a compact radial cross-section is required and where the surrounding components provide the hardened raceway surfaces; the JN cage guides the needle rollers and maintains their spacing during rotation.