Unique 23+ Under The Saddle Acoustic Guitar Pickup. This great piezo pickup is designed to fit on your bridge underneath the saddle of your acoustic guitar. Get the best deal for under saddle acoustic guitar guitar pickups from the largest online selection at ebay.com. Musiclily guitar under saddle piezo bridge pickup for acoustic guitar replacement parts. Quite honestly, these use to sound simply awful, nothing more than a single coil electric guitar pickup on an acoustic guitar.