The Meritor 3123399002 is a cast unbalanced brake drum component designed for heavy-duty truck brake systems. Meritor brake drums are engineered to work within the S-cam drum brake architecture common on commercial trucks and trailers. If you need to confirm whether this drum is the correct fit for your axle or brake assembly, call Pro Gear and Transmission before ordering. We carry genuine Meritor brake parts and can help you identify the right component for your application.FeaturesGenuine Meritor cast brake drum componentPart number 3123399002Designed for heavy-duty truck drum brake applicationsCall Pro Gear and Transmission to confirm fitment for your specific axle or brake assembly