BlueRigger via Amazon offers Prime members the Kinivo Bluetooth Hands-Free Car Kit
, model no. BTC455, for $29.99
with free shipping
. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping costs $5.99.) That's the lowest total price we could find by $17. It includes a 48" auxiliary cable, 24" extension cable, and built-in microphone.