ST60/36-36-40/32

The StopTech Rear 355 ST40 Big Brake Kit enhances braking performance. It includes Drilled or Slotted 2pc Aerorotors (355mm), 4-piston ST40 forged calipers, forged caliper brackets, Sport pads, and DOT-compliant stainless brake lines. The kit utilizes StopTech's Balanced Brake Upgrade® to optimize brake bias and tire contact by matching components to vehicle weight, master cylinder size, and weight transfer. Aerorotors feature a patented directional vaning pattern for enhanced cooling. ST40 calipers are forged aluminum with center bridge reinforcement and vehicle-specific piston sizes for optimal brake balance. The 309 Sport pads provide strong initial bite and consistent performance across a wide temperature range, suitable for aggressive street, autocross, or light track use, with less dust than stock BMW pads.