I bought this for my school, as I needed to amplify a 1/2 size upright bass. The problem is that the transducers are not thick enough to fit between the wings and feet of the bridge. Even with the included "shims", it was not enough to fit. I tried this on several different basses with the same results. The transducers are less than 1/2" thick, so unless your bridge wings are really close, there is no good way to make this work. Because the pick-ups are designed to collect sound from both the top and bottom, there is no good way to mount these other than as directed, or to buy a new bridge. If I had to do it over, I would buy the thin pickups, which slide between the feet and body of the instrument. When held to the bridge, the pick-ups have a wonderful sound, but there is really no good way to make this work.