The #1 accessory recommendation to enhance enjoyment of using a TowWhee. For quickly connecting the TowWhee to the trailing bike this small loop & great feeling climbing style carabiner make it easier & faster than looping through itself stand alone. This loop can stay on the trailing bike permanently. The carabiner stays on the TowWhee for built in storage. You can hook the TowWhee into a loop to carry over your shoulder, wrap the TowWhee around your waist twice like a belt or clip to your pack.