All the results of the simulations and the experimentations indicated that the ceramic ball bearings' performances are very good, especially in the low load and high-speed environment. Suitable for all cycling applications, whether it is road, MTB, or triathlon, these pulley wheels will optimize your speed rear derailleur with reduced friction and extended lifetime.

Features:
Suitable for all cycling applications, whether it is road, MTB, or triathlon, these pulley wheels will optimize your speed rear derailleur with reduced friction and extended lifetime.
Being the fastest spinning bearings on your bike, an upgrade with our high-performance pulley wheels are an effective way to save energy or ride faster.
Weighing only astonishing 7.7g grams, these lightweight pulley wheels are fitted with hybrid ceramic bearings, which reduce friction and feature increased lifetime.
The aluminum alloy is very practical, and together with the pulley design, the set optimizes the overall performance of your derailleur. The removable design also makes the maintenance much easier.
They are also resistant to water and salty environment and they will never need lubrication or getting rusty.
For guide pulley, we use POM bearing rings instead of steel bearing rings, POM is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability.

Specifications:
Brand: ZTTO
Material: aluminium alloy
Color: red, black, blue, gold, titanium (optional)
Fit for: 4/5/6 MM roller screw axis
Size: 11T
Item weight: 7.7g / 0.27ounce
Package size: 100 * 50 * 50mm / 3.9 * 2.0 * 2.0in
Package weight: 19g / 0.7ounce

Package List:
1 * Bicycle Jockey Wheel

Shipping:

1.We guarantee to ship goods out within 24-72 hour after