Workspec Quality Super low friction responds to top speeds.
Axon X9 Ball Bearings are the ultimate ultra low friction ball bearings with exceptional precision and minimal vibration when spinning bearings.
From slow to high speeds, the bearings spin without vibration, and stress-free so you get sharp machine acceleration and amazingly elongated top speed.
In addition, since the Axon Core Bearing Oil is pre-filled during shipping, you can use the WorksSpec Bearings in the best condition as is.

(From Amazon.co.jp)

From the Manufacturer

AXON BM-LF-011 X9 BALL BRG. 630/2pic

Axon X9 Ball Bearings are the ultimate low friction ball bearings that provide unlimited vibration when rotating bearings.From slow to high speed rotation, the bearings spin without vibration, and stress-free so you get sharp machine acceleration and amazing stretch speed.

In addition, since it is pre-filled with Axon Core Bearing Oil at the time of shipping, you can use the WorksSpec Bearings in a good condition.