I took this out of a Gibson J-45 I recently acquired - I don’t play it live so have need for a pickup in it. Tested before I took it out, worked fine. It was actually very unobtrusive when fitted, it only weighs about 100g including the battery. You’ll need a piece of self-adhesive loop velcro to attach the battery pack to the neck block, a small piece of double-sided adhesive foam or tape to attach the controls to the inside of the soundhole, and a couple of small self-adhesive cable clips to tidy up the wiring inside. Will be well-packaged for delivery.