Genuine Caterpillar breathers provide a filtered vent for the hydraulic tank. This allows air to flow in and out of the tank as needed with the change in fluid levels within the tank. For C9 models
Genuine Caterpillar open element crankcase breather element. Replaced by 380-5840. For C13 and C15 Genuine CAT 296-8325 Crankcase Breather Filter C13 C15