Wanting to use my Grandmeister 36 - which has a single amp output Jack - with two cabinets, meant I needed an adaptor to allow for this. No cables etc available, so, expected to have to make one up myself. However, came across this little box which is perfect and exactly what was needed. After receipt - it's a nice small size unit, caters for both series or parallel set ups, cracking piece of kit for a sensible amount of money. It would have been easy enough to knock one up, however, when it's all done for you, why bother - just buy it!