This is the MXR Dyna Comp, one of MXR's best-selling pedals. It's a compression pedal that allows you to enjoy intuitive sound shaping with just two simple controls. This particular unit features a block-letter brand logo and was shipped around 1980. The casing shows signs of use, such as paint peeling, a small groove for the external battery snap, and some fading of the model name print, giving it the feel of a vintage instrument. The OTA, which is the core of the sound, still uses a reliable National Semiconductor LM3080N op-amp. The protective and insulating sponge for the parts has been replaced due to deterioration over time. The warm tone, while compressing strong picking without losing the treble image, is a unique charm of vintage DynaComp. Replacement parts: Switch washer / Battery snap / Back panel mounting screws (2 missing) Accessories: None Heartman Vintage Guitars is a specialty store for vintage guitars and basses operated by Ikebe Musical Instruments.