Dinex Diesel Oxidation Catalyst for Mack/Volvo Trucks. This DOC is engineered to deliver OEM-level emission control for Mack and Volvo diesel powertrains meeting EPA10 standards. The catalyst core promotes oxidation of carbon monoxide (CO) and unburned hydrocarbons (HC) and aids in reducing soluble organic fractions of particulate matter prior to downstream aftertreatment, helping restore emission-system function and clear emission-related fault codes. Constructed from stainless steel housings and a robust metallic core, the unit is sized for heavy-duty exhaust flow and built to withstand commercial duty cycles. Typical external dimensions are approximately 12.87" long with a 12.99" diameter and a service weight near 38.8 lbs, providing a compact direct-fit replacement that integrates into existing DOC/DPF assemblies. Installing a properly matched DOC returns the oxidation stage of the aftertreatment chain to specification, which can reduce exhaust backpressure and support more efficient DPF regeneration events; these effects contribute to measurable fuel-use stability and reduce downtime associated with repeated fault conditions. The product is offered in configurations that match OE interfaces and is sold with varying accessory options (clamps and gaskets available with some SKUs) to simplify installation and minimize vehicle out-of-service time. Dinex backs the component with a multi-year warranty to support fleet asset planning. Specified for Mack and Volvo applications cross-referenced to common OEM numbers, the design focuses on durability, predictable flow characteristics, and consistent oxidation performance across a wide operating envelope. For fleets replacing a failed or degraded DOC, this Dinex unit provides a direct aftermarket option intended to restore emission function and operational consistency while aligning with EPA10 aftertreatment expectations.