YFB connecting rod supporting needle and cage assembly can provide the following Series: K, KK, KZK YTB connecting rod supporting needle & cage assembly is applicable to the medium and small size diesels. The needle bearings , due to its special operational conditions , must bear the shock force from the explosion in the cylinder, the inertia forces of the piston, the connecting rod and the crank shaft. Therefore , needles and the retainer must sustain the great centrifugal forces and acceleration forces. Besides, it is responsible for the heat dissipation. So, the flow of lubricant oils must be taken into account during the entity designing of the bearing so that enough cooling area is increased , or coating copper, silver on the surface to prevent the abnormal abrasion during the starting period. To conclude, the connecting rod supporting needle retainer assembly has the following merits: light weight, lower inertial force, the use of highly anti-fatigue, highly rigid and highly abrasion-resistant materials, low abrasion force in low speed operation and high cooling capability. Roll packing or single box