This is in really good condition and no longer made - if you want one, you have to buy used. The MDB-1 allows you to plug in three different instruments to your amp and balance the levels. It also adds a REALLY nice DI and and effects loop. Powered by two 9-v batteries, you get about 50 hours of time. It is clean, flexible and a real problem solver. I'm asking $[DEL]225[/DEL] 210 shipped in the US. I'll be posting pics but I have some photo editing to do first - the file size on the pic is HUGE. Let me know if you have questions! Dan K.