I've used many of the options listed in this thread, but my
personal preference is the following:
(Note: personal preference has no place in DIR team diving and will get you killed
)
3/16 Latex surgical tubing w/ 1/8 interior diameter & 1/32 walls
- w/ the smaller latex surgical tubing you can skip the zip ties & simply tie the ends to each other, creating a loop around the mouthpiece
- small latex surgical tubing is very tough and elastic, and yet can still be broken if needed
- I also prefer the small latex surgical tubing (over shock cord) for holding my backup lights in place b/c the latex grips them much better
Here's another good place to order tubing if you know the exact type you want:
Surgical Tubing Latex Surgical Tubing reefscuba.com
R/g shock cord - It's very difficult (almost impossible) to break and is thus well suited for many applications: holding corrugated & LP hose, bungee for compass, computer, slate, etc.). However, b/c I can't easily break it if needed, I'm not inclined to rope it around my neck
But hey, I'm just another DIMWIT diver, so do what works best for YOU