The Hawk Performance ER-1 (Endurance Racing) series is a high-performance motorsport brake pad designed for maximum consistency and longevity under extreme racing conditions. This set (HB521D.650) utilizes a premium friction material specifically engineered for endurance racing, offering a high coefficient of friction throughout a wide temperature range. The kit includes: 1x Front Axle Brake Pad Set (4 pads), Hardware Kit (where applicable), and High-Temp Lubricant. Features Include: Superior modulation, excellent thermal stability, and reduced pad wear for extended race sessions. Compatible with FMSI D1107 brake systems.