So my OBA system has a pair of threaded bulkheads on the rear bumper…
The left bulkhead has a hand valve behind it and is used for airing up tires, running air tools, etc.
The right bulkhead is connected to a solenoid valve and is mainly used for draining the moisture out of the tank at the push of a button, but it also works great for scaring the $#!t out of cats 
Anyways, our work contract at the bus yard ran short of supplies, so I’ve been slumming it at the shop for the past few days :o
It’s been really slow and after shooting off some potatoes with the spud gun to pass the time (always good fun), I decided to turn my OBA fitting into a weapon using some left over brass tubing and some Nerf darts I had laying around 
https://www.youtube.com/watch?v=_1m2XlNClrE
Should be fun at Best Buy on Black Friday 