SKF - MTRX Bearing - 6806MTRX The new standard in bearing technology. Based on decades of experience in industrial applications, SKFs MTRX solid oil bearings are the most reliable and durable solution for mountain bikings most highly contaminated and wet environments. MTRX bearings are filled with SKF Solid Oil technology. The oil impregnated polymer matrix lubricates and protects the bearing even under the toughest operating conditions and ensures significantly longer