Amazon.com: Motorcycle Helmet Lock & Cable. Sleek Black Tough Combination PIN Locking Carabiner Device Secures Your Motorbike, Bicycle or Scooter Crash Hat (and Jacket) to Your Bike. : Automotive
Harley-Davidson Helmet Lock | Harley-Davidson USA
For those asking about helmet locks, some of you (Americans) may already have one : r/motorcycle
Amazon.com: KEMIMOTO Motorcycle Helmet Lock with High Security Combination PIN and 60in Helmet Lock Cable for Motorcycle Helmet, Bike Helmet, Jacket and Bag : Automotive