1807350 Pin-Piston Fits Caterpillar ModelsOne New Aftermarket Replacement Pin Piston Fits Caterpillar (Fits CAT) C15, C18, C27, C32 and Large Equipment Engines This piston pin (wrist pin) connects the piston to the connecting rod inside the engine cylinder, transmitting combustion forces through the engine's reciprocating assembly. It is Fits Caterpillar C15, C15 Acert, C16, C18, C27, C32, and 3406E engine families as used across a wide range of Fits CAT heavy equipment and power generation