Maxon AF-9 This is a vintage-style auto-wah pedal with a thick, present sound, using a photocoupler circuit. It allows for a variety of filtering settings. By setting the RANGE switch to Low, the filtered range can be lowered by one octave, making it compatible with 7-string guitars and basses. The condition shows noticeable scratches, but there are no issues with its operation. The unit only. Thank you. Type: Electric Guitar