I got the fittings in.
From left to right, you have the sleeve, the acrylic cap, the receptacle that screws onto the G1/4 port, and a right angle G1/4 adapter for scale.
To use the fitting, you have to glue the acrylic cap to the end of the acrylic tube, then slip the sleeve over it. The cap provides a lip for the sleeve to grab onto and stops it from slipping out. The sleeve then screws onto the receptacle, and the receptacle has a flat rubber washer that prevents leaks. The sleeve is made out of solid, heavy metal like you would expect a fitting to have, but the receptacle is made out of a lighter, thinner metal that almost feels like plastic.
The fitting is so strong primarily because of the glue. In the Youtube video, the designer mentions that you need to apply the glue evenly around the acrylic cap without any gaps or air bubbles. This is pretty crucial because the cap is what allows the sleeve to tighten down and compress the end of the tubing against the rubber washer on the receptacle. It's a compression fitting, but unlike your typical compression fitting that clamps around the tube, this one compresses the end of the tube against the washer.
Compared to the Primochill compression fitting, it's slightly longer:
But it also has a slightly smaller diameter than the Primochill fitting:
Both blend in quite well with the Bitspower black sparkle fittings:
The notches on the front are to help you tighten it down. If you buy the 6-pack (or the 4-pack if you go for the chain gun style fittings), it comes with a tool that either allows you to tighten it using the notches in the front or the holes on the side.
Once I get my caliper in, I can take some measurements.