This is another special purpose shrinking of the L-4. This was even smaller than the L-5, only 7' x7', and was only intended for observation and installation on towers. Because of the size differential the L-6 really does not have the distinctive look of an L-4. Also, most were modified. Many did not have the hinged shutters of the L-4 and the ones I have seen had a flat roof of painted canvas. The cab on the 83-foot tower on Black Butte, Deschutes NF, is an L-6.