Lifting strakes are angled, concaved aluminum rails welded lengthwise along the pontoon tubes. As the speed increases, water pushes against their formed surfaces, creating upward lift. This raises more of the tubes out of the water, reducing the metal surface drag.
Lifting Strakes allow faster acceleration and less plowing. Reduce spray due to being higher for a drier ride. Better fuel economy at cruising speed. It can hit waves harder at speed. Motor height is important.
Lifting Strakes may be welded on after, but should be done by a marine aluminum fabricator, not general-purpose welder.