Feature precision-arranged needle rollers retained by a cage structure without inner/outer rings, utilizing machined surfaces as raceways. Provide high radial load capacity and compact design solutions for limited space applications. Require hardened and ground mating surfaces for optimal performance.

Common Types:
Single row type (K, KK); Double row type (KZK, KKK); With inner ring (FW); Without inner ring (B); Sealed variants (KS, KSL); Steel cage (Suffix C); Polyamide cage (Suffix T).

Typical Applications:
Automotive transmissions, motorcycle engines, planetary gear sets, industrial gearboxes, compressor crankshafts, hydraulic pumps, robotics joints, and agricultural machinery drivetrains.