Proven time and again in World Cup race conditions, ZERØ Ceramic bearings are the ultimate race day weapon. Silicone Nitride (Si3n4) Grade 3 balls roll on Black Oxide races ground to a mirror finish after receiving Magnetite and Cryogenic treatments for hardness and longevity. ZERØ ceramic bearings feature the roundest balls you can buy without a military license and with virtually undetectable rolling resistance, they are closing in on the magic “zero” resistance wattage number. Double silicone VV seals protect the bearings regardless of weather and are lighter and more flexible than rubber, and are the lowest drag seal available. ZERØ bearings get more email and blog feedback than any other model we make citing a dramatic improvement in rolling speed.