Premium STD connecting rod bearings engineered for C7.1 engines, crafted from high-grade alloy steel with precision machining for optimal load distribution and friction reduction. Features advanced surface polishing technology enhancing durability under extreme pressure conditions. Direct replacements for OEM parts 387-2156/3707998/450-5996 with perfect compatibility. Ideal for heavy-duty applications in construction equipment, marine engines, and industrial generators. Manufactured with micro-groove oil channels for superior lubrication in high-RPM operations. Corrosion-resistant coating extends service life in harsh environments. Includes thermal-stabilized design to prevent deformation during prolonged operation. Trusted solution for fleet maintenance and engine rebuild specialists seeking OEM-quality performance at wholesale pricing.