Proto Murder 4-Pack Kugellager

Ultra-Ceramix bearings are the gold standard in bearings.

Featuring ceramic ball bearings instead of steel; The Ultra-Ceramix ball bearings are made from grade 5 silicone nitride which can be manufactured into a more perfect spherical shape reducing friction massively.

In statistical terms, ceramic ball bearings are 58% lighter, 120% harder, 68% stiffer and 75% smoother than steel bearings, and are therefore faster, more durable and ultimately far superior.