It is widely regarded that increased visibility equates to increased safety. To that end, Bell has taken their classy all-rounder, the Formula, and incorporated a bright, 20-lumen rear LED into the fit system. It's unobtrusive, highly visible, easily rechargeable with an included micro USB, and it just might make the difference between being seen and not. 

• Impact Management: Mips® Evolve
  
• Reflectivity: Integrated reflectivity
  
• Chemical Composition: Stainless Steel Lithium
  
• Circumference: 52-56 cm
  
• Construction: Fusion In-Mold polycarbonate shell
  
• Battery Type: Lithium Ion
  
• Fit System: Float Fit LED™
  
• Product Weight - CPSC: 303g (Size M)|CE: 283g (Size M)
  
• Certification: Complies with the US CPSC Safety Standard for Bicycle Helmet for Persons Age 5 and Older