I wanted a strap to hold my gopro hero 3 to a gimbal I am going to make to fit on a quadcopter.
I liked the one made by Zmooth http://www.thingiverse.com/thing:63175 but I only had some 25mm wide velcro strap so made a new one from scratch in the same style.
Printed at 0.2 layer and 40% fill with raft and came out ok.
The side with the 1mm under cut goes at the bottom to help the strap clear the camera front.
I used as piece of 25mm wide Velcro to secure it.