The Swiss plate geophone (SPG) system has been installed and tested in more than 20 steep gravel-bed streams and rivers. and related studies generally resulted in rather robust calibration relations between signal impulse counts and transported bedload mass. Here. we compare this system with three alternative surrogate measuring systems. https://www.bekindtopets.com/hot-savings-Pet-Odor-Exterminator-Candle-Sugar-Skull-13-oz-hot-grab/