After thinking about it, the design looks like it keeps dust, water, and other debris from getting down around the o-ring area, which the nyloc should do the same thing. I found a video of a guy using a socket slightly larger than the line fitting, to push the piece on. Since I've got them, I'll giv...

And, is there an easy way to install them? It seems the diameter of the holes in them are smaller than the tube they fit over, and I end up bending them multiple ways while getting them onto the lines.

Thanks