It's a mixer! It's a splitter! It's the Behringer Ultralink Pro MX882!
This is a handy gadget, a "life saver" as many musicians and sound engineers have called it. It has two main functions which have already been mentioned, mixing and splitting. In split mode, you can take a stereo signal source and plug it in via the XLR main inputs. You can then use the outputs on each channel to send that stereo signal to wherever it needs to go. The pan knob sets the levels of left and right from the main inputs. Meanwhile, if you use it in mix mode, you can plug in up to 6 signal sources, one for each channel. Then use the main outputs to send the mixed signal to wherever it is you need it to go. Use the pan knob on each channel to decide the prominence of each signal in the left and right outputs. You can expect the MX882 to live a long life thanks to being built with high quality components and rugged construction that you'd expect from Behringer.