The piezo transducers give you the flexibility to achieve the sound you want. Internal or external jack. The TGAT is supplied with a jack which can be fitted permanently internally or attached externally by the mounting sleeve supplied.
Belcat Single Transducer Bug Pickup for Acoustic Guitar
TGI Single Braced Keyboard Stand, Black (NEW)
Thumb Piano Transducer Acoustic Guitar Pickup Piezo Microphone Finger
Thumb Piano Transducer Acoustic Guitar Pickup Microphone Finger
PIEZO PICKUP ARTEC PP333 under Saddle 3 + 3 Split Transducer Acoustic Guitars.
TGI Soundhole Pickup Acoustic Guitar
