We have a 19″ Feather stream propeller with adjustable pitch. Works really good both forward and astern. The boat stops in no-time. It also hasthe possiblility to swap pitch-casette. Really handy when you are trimming the prop. When we first got it the D2-55 didnt manage to reach max RPM which is a sign of that the prop is over pitched (initial setup is a guess). Did order a new pitch-casette, took 10 minutes to change it and now the prop is correct set. Can not point our enough the help i did get from Darglow engineering (manufacturer of the prop), both before the buy and the afer service.