Product PA411 not in drop down ?

Hi All, I have a new ethernet only installation at home. The AV600 Pair of Powerline Adaptors work great though as always someone has to push the boundaries. I am passing through a power board that is a 'no no' apparaently, however it does work and well for me, except.. I can not get the extra 30 metres I need, probably due to losses ?. Question is can I purchase another pair of AV600 and simply plug one of each pair directly into eachother so one adaptor is the other side of the power board and the last pair adaptor is 30 metres away. So just for clarity    av600..........(powerboard).......av600 - ethernet cable - av600.........(30m).........av600.

Look forward to hearing