Disappointing: do not purchase!
The pairing is finicky with my iPhone 6. When I switch on the Sharktooth, it pairs properly, but loses the communication immediately. I have to unpair and pair it again each time. I do not know if this is because my iPhone 6 is an older model, but I have other devices that pair with it and don't lose connection as the Sharktooth does.
Second issue, and this one is inadmissible. The volume level is inaudible above 30 miles per hour. My helmet is the Shark Race R Pro Carbon, among the most quiet ones. With full volume on both the phone and the Sharktooth, I cannot make out the driving directions.
I do not recommend purchasing the Sharktooth Prime.
I am looking for Bluetooth in ears that can fit my helmet.