Markbass compressore tube bass compressor. Comes with original box, power supply and manual. This thing sounds so good-it really thickens up your sound in a beautiful way. I know I'll regret selling it soon but for now it's not getting any love due to my changed set-up. I installed a Mullard "cryogenically treated" tube and and it sounds just amazing (a $40 tube!). It cleared up the overall sound compared to the original tube. I will also include the original tube-it's a JJ brand. The unit works perfectly and is in nice shape with just a few marks. $169 Price includes shipping in USA. I ship FAST and pack very carefully.