Check www.biosdrive.com for more information. Top hearing speed is 130Km. Guess where are the two speakers? They aren't located at glove box. Actually, they are located at the ventilation window at each side.So, I" kept two glove boxes for the owner.He is very happy with it. However, the Burgman helmet compartment is sealed very tight. I have to enhance the sub-woofer from 5.5" to 8" in order to push bass overflow from the compartment.