EBC S4KR1621 S4 Rear Disc Brake Kit Redstuff Ceramic Pads and USR Slotted Rotors

The EBC S4KR1621 is a complete rear disc brake kit combining EBC's high-performance Redstuff Ceramic Sport Brake Pads with USR Fine-Slotted Sport Rotors for a significant upgrade over factory braking components. This S4 kit is engineered for drivers of muscle cars and premium imports who demand shorter stopping distances, less brake dust, and quieter operation.

Redstuff Ceramic Brake Pads:

• Built with Aramid fiber enhanced with ceramic granules for superior braking power and reduced dust
• Fully shimmed, slotted, and chamfered for ultra-quiet performance
• Features EBC's patented Brake-In coating for fast pad seating after installation
• High heat threshold with strong initial bite and zero brake fade
• Centerline slot vents cool air to prevent thermal cracking
• Covered by EBC's 12-month / 10,000-mile warranty

USR Fine-Slotted Sport Rotors:

• Fine slotted rotor surface promotes silent braking and improved cooling
• Dual slot pattern ensures flat and parallel pad wear, eliminating ridges and grooves
• Vented center design allows even heat expansion and minimizes warpage risk
• Finished with Thermic Black anti-rust coating — no removal required before installation
• Fully balanced and runout-tested for smooth, vibration-free braking

Kit Contents:

• EBC Redstuff ceramic rear brake pads
• EBC USR slotted rear rotors (pair)
• Brake caliper lubricant

Installation Note: Do not fit upgrade pads to the rear of the vehicle unless the same upgrade grade is also fitted to the front. The Thermic Black coating on the rotors does not need to be removed before installation — it will self-clear in the pad-swept area within the first 10–20 stops. Do not use brake cleaner or any other method to remove this coating, as doing so voids the EBC warranty. EBC recommends a 500-mile break-in period with moderate braking after installation.