The B&M  Line E Brex E-Bike light has an integrated sensor system to detect braking action.  The sensor is ultra-sensitive, and In the event of abrupt emergency braking, the brake light switches up another level to the brightly pulsating emergency brake light function. In this mode, BREX conveys the dangerous situation with an unprecedented signalling effect and prevents accidents.

Unlike traditional brake lights, this system requires no direct wiring to the brake system. 

Specifications:

• Weight: 50 g
• Dimensions: 32 × 94 × 45 mm
• 6-50V DC, 1.7 Watts
• 50mm spacing.