This is a select loop pedals of effects that can also be used to connect multiple instruments or instrument amplifier on several amp. A sort of Swiss army knife of sound. It can be used to power other pedals intermdiaire by a multi cable alim.
The PDAL has no direct effect on the sound but works as a router. I think this is a useful tool really trs.

Operation is simple: 2 + dparts effect returns that can be used also as between suplmentaires for a 2nd instrument or as dpart suplmentaire for a 2nd amp. A slecteur can vary the types of routing the sound: Channel A or B, Channel A + B, Etc. ..
The leaflet provides a choice of types of configuration.

Grace the pedals, I finally found my sound I was looking for a way to shuffled the sound of my effects loop with a direct guitar (the one Manir dpart auxiliary console) and send it in a single channel amp (my amp has one channel). I find my Holy Grail with the LS2. Thank you Boss.

It became the foundation of my sound of scratching. Moreover, this is downright transparent pedals. The possibility to feed my effects loop is a more carrment practical lugging a single adapter.
How could I do without?
It is in the $ 100 new. An essential investment in me.