In the PXL Pro, you have 8 programmable loops for your guitar effect pedals. You can set the PXL up as one series loop of 8 or you can split them into 2 loops of 4 and use effects in your FX LOOP.

This means that loop one can be for your pre amp effects (OD, distortion etc.) then loop two can be plugged into your amps FX loop and used for post amp effects (modulation, delay, reverb etc.)

Another great feature of the PXL Pro looper is the 4 switch triggers. This means that you can control up to 4 switchable functions on external devices right from this looper via 4 1/4 inch jacks. These might be amp channels, effect modes. 

You can even program each trigger to latch or make a momentary contact and you can also set the polarity (Normally open/Normally closed). Some amps may need a custom cable to work with this looper.

Other great features include a mute/tuner out switch. You can store up to 32 different effect sets, all the combinations you can think of, or even bypass all loops with a single stomp.