This is an iRig acoustic guitar contact pickup system. You just clip it into the soundhole of a vintage guitar or similar, so you don't have to drill any holes. I used it on three vintage guitars, but I sold two of them, so I no longer need it. It has been transported and stored in its original box, so the outer box is worn, but the main unit and case are almost clean. Please refer to the photos for the condition. Operation has been confirmed. The AA batteries in the photo are for testing purposes, so please use new ones when you use it. Please understand that this is a used item. Thank you. [From the Soundhouse description] The iRig Acoustic Stage consists of a MEMS microphone mounted on a small clip the size of a guitar pick, and an advanced digital preamplifier unit with DSP functions. Setting it up is very easy. Simply attach the MEMS microphone to the soundhole, connect it to the iRig Acoustic Stage's preamplifier unit, and then connect the preamplifier unit to an amplifier or mixer, and you'll have a rich, studio-quality sound on stage. It's an innovative digital microphone system. ■ Clip-on MEMS microphone that can be attached to the soundhole. ■ Preamplifier unit with DSP functions. ■ 1/4 inch AUX input jack for connecting to onboard pickups such as piezo/magnetic. ■ 1/4 inch audio output jack with volume control. ■ Equipped with a USB audio output jack (micro-USB) for recording on computers and mobile devices. ■ Equipped with a feedback prevention function (Cancel Feedback button). ■ 6 types of sound presets. ■ Supports custom calibration function. ■ The clip supports up to 4mm thickness, allowing the microphone to be attached to acoustic, electric-acoustic, ukulele, etc. ■ Equipped with a phase switch to optimize the sound when inputting from two sources.