This is a custom made-to-order onboard Trinity System from K&K for acoustic guitars and similar stringed instruments. It's exactly the same as the regular Trinity system, except with a preamp made to go inside the instrument and a single mono output jack.

I ordered it directly from K&K a few years ago, and have since pulled the mic, preamp, and controls out of a guitar and bought a brand new Pure Mini pickup to use with it. So it's slightly used except for the Pure Mini, which is brand new. Fully tested and everything works great.

This system sounds incredible and can be dialed in perfectly with the preamp's adjustable gain/bass/mid/treble for both the mic and the under-bridge transducers. The mic and transducers can also be blended with separate volume knobs.

Comes with everything pictured: the pickup system, manuals, tool for turning the EQ knobs when it's in the guitar, some velcro/dual-lock, and an extra endpin strap lock from Acoustic Strap Secure.