Quick release mechanisms are very common on military gear. More often they are found on ruck sack straps. They come in useful if you are ever injured or caught up in something and you have to remove your pack quickly. This "high speed low drag" pin replicates that same quick release action.
Note: "High speed low drag" is a military talk for "cool".
Step 1: Start with 3/8" Aluminum rod.
The overall length of this pin is about 1&1/2". I cut off about 3" to work with. If you do like I did and use a pipe cutter in a lathe use extreme caution and at a very low RPM.