Loud and solid. Cord too short.

The Shaker is the coarse variety. One has even shake vigorously, then the ball dissolves inside the magnet on the top. For arritieren to the shaker must again hold so that the ball falls upwards. Unfortunately it needs an additional carabiner or similar for fastening the jacket, because you can not pass through the loop it. After just a few dives to the string node has solved itself (thankfully ashore). Since the eye is very sharp, I recommend these to file around and to take a longer cord for the shaker can be easily attached to the jacket. There may also occasionally happen that the balls come off by itself.