This hands-free set for mobile phones provides comfort and security while biking. There is no pinch on your ear due to the very flat speaker pads. The model HS-310 is most suitable for your full-face helmet. The microphone is fixed in the mouth area by Velcro tape. Our model HS-330 is best for your open face or flip-up helmet. The flexible boom keeps the microphone in the optimal position. The very useful coiled connection cord with waterproof mini-DIN-connector allows you hiding the mobile phone in your leather suit. Both hands-free sets are equipped with a 2.5 mm phone jack. Possibly needed specific mobile phone adapters are available at any good electronic store.