R1 Concepts 623-45003L RNC Series Drilled Disc Brake Rotor - Left

The R1 Concepts 623-45003L is a precision-engineered drilled disc brake rotor from the R1 Concepts RNC Series. Designed as a direct-fit replacement, this single left-side rotor delivers enhanced braking performance over stock, with no modifications required for installation.

R1 Concepts manufactures this rotor to OEM dimensional specifications using G3000 grade cast iron, providing the strength and thermal stability needed for consistent, fade-resistant stopping power. The rotor features a precision-drilled hole pattern with countersunk edges to maximize heat dissipation while minimizing the risk of stress cracking under repeated thermal cycling.

Key Features:

• Drilled Design: Precision-drilled holes allow heat, gas, and brake dust to escape quickly, reducing brake fade and improving wet-weather performance
• Countersunk Drill Holes: Engineered to reduce stress concentration and prevent cracking at drill hole edges
• G3000 Cast Iron Construction: OEM-grade material for optimal friction compatibility and long service life
• Zinc Plated Finish: Protective zinc coating on the hat and non-contact surfaces guards against corrosion and rust
• Direct-Fit Replacement: Designed to match OEM mounting dimensions — no modifications or adapters needed
• Left Side (Driver Side): Sold as a single rotor; confirm correct side before ordering

This rotor is compatible with both OEM-specification brake pads and performance aftermarket pads. For best results, R1 Concepts recommends replacing brake pads at the time of rotor installation and performing a proper bed-in procedure to seat the new friction surfaces.