I added a few of my own touches with a redesign of the original. Holds 1.3" wide straps and has a small detent to hold the two parts together. Also, i added a reel post to speed up the winding process. the reel post is optional; the reel is easy to use with or without it.

Edit: Increased height of bottom post so that the assembly stays together a little better.

Change horizontal expansion setting -0.05 to -0.1 if your fit is too tight.

Edit: Reduced diameters on winder by .25mm