 It is the Piazzo driver amp Stema PAM 8904. Here are the little gain switches. This actually is a AC element and so it doesn't really matter which wire gets plugged in where. We have a 3-pin JST and plugging that into a Metro RP2040 there and you can see I've got my 3 volt power ground and then I'm running off of pin D5 and do a little reboot. You should be able to hear that pretty well. Quiet this thing a bit so that's the 1x gain and that'll turn it off. And that is it. That is my product pick of the week. This week it is the Stema Piazzo driver PAM 8904.