Reminds me of an avalanche device I bought about 30 years ago in the ‘balloon’ category. It was more discrete than the McDonald’s party and consisted of an armband with an inflatable orange balloon wrapped in a plastic soft shell. In case of an avalanche, we were supposed to pull it, a chemical reaction (I guess more of an explosion) would inflate the orange rubber ballon, still connected to the armband by a few meters of thin nylon cord.
I had always wondered if I would and could pull it if caught, and whether it would work. A few years ago I found it when packing things, and tried: it worked - and worked well - after all these years. Then the questions remain about the ability to trigger it when caught, and whether following a cord in an avalanche is effective, and also if the balloon, or the cord, or the armband - or the arm - could resist the forces at play in a serious avalanche…
Apart the ABS which has a different objective (floating above the avalanche and being somewhat protected) it doesn’t seem anything succeeds in the avalanche device market other than the ARVA?
Stay safe!