The Seda Amigo was designed as a hybrid solo/ tandem sea kayak.

It is 18' long, 25" wide

I wouldn't want to paddle it in really bad conditions, but it is the
best attempt I have seen so far. There are inherent contradictions in
creating a solo/ tandem kayak and it compromises as best it can.

A review can be found at
http://www.canoecolorado.com/kayaking/seda/amigo/

The Manufacturer is Seda Kayaks http://www.sedakayaks.com