R1 Concepts 830-58039L DFC GeoPerformance Drilled and Slotted Brake Rotor - Left

The R1 Concepts 830-58039L is a DFC GeoPerformance Drilled and Slotted Brake Rotor featuring a combination of cross-drilled holes and machined slots for enhanced braking performance. This is the left-side (driver's side) rotor, identified by the "L" suffix in the part number.

GeoPerformance Design Features:

• Cross-Drilled Holes: Chamfered drill holes reduce heat buildup on the rotor surface and help dissipate gases during braking
• Chamfered Drill Holes: Reduces the potential for stress cracking at the drill points for improved long-term durability
• Machined Slots: Remove brake dust and road debris from the pad surface, prevent pad glazing, and provide increased bite — especially in wet conditions
• GEOSPEC Corrosion-Resistant Coating: Applied to the entire rotor — including the hat, vanes, and non-contact surfaces — to protect against rust and corrosion
• Dry-Shipped Ready to Install: The GEOSPEC finish is processed dry and shipped dry, requiring no cleaning or prep before installation
• G3000/G11H18 Cast Iron Specification: Engineered to match OEM specifications for strength, stability, and durability
• 100% Electronic Inspection: Each rotor passes an electronic inspection station measuring over 20 attributes to ensure OE-specification compliance
• Non-Directional Surface Finish: Promotes faster and more even brake pad bed-in for quieter, smoother stops from day one

The DFC GeoPerformance series is sold as a single rotor (per qty: 1). The 830-series designation confirms this rotor features the full drilled-and-slotted treatment with the premium GEOSPEC corrosion-protective coating — delivering a performance upgrade over standard blank rotors while maintaining street-friendly reliability.