Matrix Infinity with Acoustic Matrix Under saddle Pickup in narrow 3/32 " (2.3mm) format PRO-MAN-INF Completely redesigned active, endpin mounted preamp Sound hole mounted rotary controls for Volume & Tone Unique Tone control cuts mids while boosting treble and bass Integrated LED low battery indicator Features the world's best selling under saddle pickup, the Acoustic Matrix Switchable voicing to accommodate all guitar body sizes & performance situations Available in two saddle slot widths: wide 1/8 " (3.2mm) format or narrow 3/32 " (2.3mm) format Standard overall length of 2.65 "(67.3mm) will fit most guitars with string spacing's of up to 2.5 " (63.5mm) Solderless connections Professional installation is recommended Requires 9V battery (not included)