Hirobo HI2500070 Ball Bearing 3 x 9 x 3 mm open type, 2 pcs  [HI2500070]

Ball bearing for RC helicopters

This is an RC-scale ball bearing set intended for general-purpose helicopter maintenance and small linkage pivots. The item corresponds to the HI2500070 designation and is supplied as 2 pcs of open type bearings sized 3 x 9 x 3 mm, suitable for replacements where compact bearing housings are used.

In practice these bearings serve as low-profile rotating support in rotor assemblies, swash linkages, control arms and other small pivots. When replacing bearings, verify seating diameter and axial clearance on the hub or linkage to avoid binding. Check the mating bore for wear or deformation before installation.

Installation tips: press the bearing straight into the host bore using a soft drift or bearing driver sized to the outer race, avoid applying force to the inner race, and confirm free rotation after seating. Use light rotary oil sparingly on open bearings if exposure to dust and grit is low, otherwise plan periodic cleaning and re-lubrication for service life.

This product is presented as an RC accessory component, not for full‑scale vehicle application; use it only on model aircraft and compatible scale components.