I have a Bose Mini Soundlink BT speaker I may use first off. I just put it up on the dash in my Hummer if I want to listen to music/podcasts via my phone. Not super loud though.I got the impression it wasn't specifically for JBL and more of a holder for a generic cylinder shaped BT speaker. Like perhaps there is some flex in it so it can open wider to accommodate a range of diameters. I am hoping for that because I already have a non-branded JBL like BT speaker that I plan to use in my Slate.