In 2009 I walked into Guit-ard Center planning just to buy strings & ended up with a VM Fret-less JBASS. It is a fun bass stock but as usual for me it wasn't long before I started modding it. In the first 2 or 3 years I added EMG pups, Badass bridge, Dtuner, all stainless screws & eventually a fretted neck from a Pbass Special. (Pbass Special is fret-less now ) Fast forward to 2016: I got the erg to mod this bass a bit more so I grabbed a EMG BTC system. The pup blend pot was the carrot for me to upgrade to the BTC setup. I got all ready to install & quickly realized that the BTC wasn't going to fit in the control cavity with a 9v battery in there with it. Actually it barely fits without the 9v. So I started weighing my options. I didn't really want to go the router route. I starting looking at different battery options & there is really not any plug & play options out there that I could find so I made my own ... BTC System is a tight fit DIY Battery Adapter 3 CR2032's gets it done ... fits under the volume pot ... should last at least 6 months All Done New Mighty Mite neck finishes it off.