Yoke type track rollers STO have an inner ring. Depending on the design, yoke type track rollers are also available as sealed versions. Bearings with an inner ring are used if the shaft or stud does not have a hardened and ground raceway. Series STO is not self-retaining. This means that the outer ring, needle roller and cage assembly and the inner ring can be fitted independently of each other. This gives simplified mounting of the bearings. The rolling elements are guided by the cage. These designs do not have axial guidance of the outer ring. Axial guidance of the outer ring and needle roller and cage assembly (for STO only) must be provided in the adjacent construction. INA Track Roller, Crowned Yoke Type, Series: STO, 12 mm Bore, 32 mm Roller Diameter, 11.8 mm Roller Width, 12 mm Overall Width, 10300 N Load, Open Closure, 4500 RPM Maximum, -30 to 140 °C, Uncoated