UPDATE 12/21/21: Increased the tolerances at the hinge and strengthened the clasp.

Remix of freakinhuge's Cable Clamp thing:3923

I made a few modifications, adjusting the tolerances of the print-in-place hinge and simplifying the clamp latch. I also positioned it so it would print opened. I've included 2 designs, one with a hole for hooking onto a wall or something and one without.

Printing:

I printed several, all in PETG at 0.16, 0.2, and 0.24 layer heights on my Ender 3 v2.

Support is necessary at the toothed end touching the build plate. You may also want to support the bridged area of the clasp but there is some tolerance build in for sagging. If you print the loop version you may want to support that also. DO NOT support the hinge as this will cause it to fuse. Use a support blocker in your slicer for the hinge.

Use bridge settings. Prusa slicer has bridge settings and Cura has then under "Experimental". The cura bridge settings worked for me.

125% seems to be a good size for extension cords and air compressor hoses.