Cardo Freecom X / Spirit 2nd Helmet Kit JBL 40mm The Cardo Freecom / Spirit 2nd Helmet Kit allows you to mount your Freecom / Spirit headset to another helmet. Features Compatibility: Freecom 2X, Freecom 4X, Freecom 1+, Freecom 2+, Freecom 4+, Freecom 1, Freecom 2, Freecom 4, Spirit, Spirit HD 40mm JBL Speakers Boom and wired microphones included Suitable for all full face, modular and 3/4 helmets