CONSTRUCTION: Virtually unbreakable dual compound body MOUNTING SYSTEM: Front: Quick release bracket fits rigid or suspension forks with steer tubes 18.5 – 49.6 mm. Rear: Adjustable Boa Bracket fits all seatpost/seat tube diameters. ADDED BENEFIT: Front: Independently adjustable front and rear flaps. Rear: Raised mounting spine enhances stiffness and reduces chatter; 3M reflective panel for nighttime visibility; dual pivot design offers easy adjustment to fine-tune positioning