340-024 is a National axle hub cap, a heavy duty cast aluminum truck hub cap. The cap covers the end of the hub and keeps the wheel-end lubricant and bearings protected from road dirt and moisture. Pro Gear and Transmission sells it as a genuine National part. Call us if you want help matching it to your axle. It is listed in our National Seals category alongside other National sealing and wheel-end parts.FeaturesNational axle hub capHeavy duty cast aluminum constructionTruck hub capGenuine National partTech SpecsBrand: NationalPart type: Axle Hub CapMaterial: Cast aluminumDuty: Heavy duty truck