FYI I found this design to be bad; it vibrates a LOT. I suggest trying this newer design instead:https://youmagine.com/designs/bicycle-tail-accessory-mountWorks with the Topeak quick release rack trunk bag and GoPro mount compatible cameras.I bought a SJCAM M10 for rear-facing video on my commuter, then realized that with the rack trunk in place, there was no place to mount a camera that didn't get blocked by the bag.