This is a Nyos quantum 120 protein skimmer. It is brand new, never taken out of box. I realized before It was even delivered, that it was going to be to small for my tank. Retailer and wholesaler would not take it back, which is a whole nother story I would rather not get into. I have the Quantum 160 in the tank now and it works great. Really is a top quality skimmer for a reasonable price. Im asking 300.00 simply cause it's going for over 400.00 retail and this thing is straight from factory, never opened.