For sale Radial Phaser

I recently purchased this item new from Sam Ash. What does it do? It works great to make your bass amp work better with the foh subwoofers in small to medium venues. You know that scenario where your sound checking and when the bass gets brought up in the foh the low end gets hollowed out? This device can stop that. After trying a few different DI’s and preamps I’ve decided to go in a different direction. Absolutely mint condition. Will consider trades for Shure KSM8 mice, lr baggs venue di, Grace designs Alix di. Or, $250 shipped in the 48 states.