Connecting rod bearings are precision cylindrical components installed between the connecting rod and the crankshaft journal. They facilitate a low-friction, pivoting articulation enabling conversion of piston motion into rotational force. These bearings are typically constructed of layered steel backed with a babbit alloy or polymer coating to withstand high loads and speeds. Variations include bi-metal, tri-metal, and polymer designs, differing in material composition and load capacity. Dimensional accuracy and surface finish are critical for proper oil film maintenance and preventing crankshaft damage. Proper installation requires precise clearances verified with plastigauge or similar measuring tools.