This is a vintage (circa 1981) Ibanez Tube Screamer Overdrive Pro TS-808 guitar effects pedal by Maxon. This very rare version, serial number 144526, features the highly coveted Texas Instruments TL4558P chip, which also famously powered the orange-colored Ibanez OD-1. Those who contend that the results of an A-B test between the various TS-808 chips will produce results that suggest they sound nearly identical… need to have their hearing checked. To my ear, the TL4558P chip is the obvious winner. While surely sonic preference is subjective, I feel the TI chip is of higher quality producing a more pure signal with harmonically rich overdrive. Some 808s can be sterile and not very dynamic, but such inadequacy does not plague those rare specimens with the aforementioned chip. As can be seen, this pedal is in good all original condition. It appears the battery clip was replaced, but it is otherwise in 100% original condition.