Nordic Kayaks provides four rudder options for its ski and kayak range
Surf - the largest and most dynamic. Most suite to those looking for more depth and purchase or a little more resistance to rolling
Weedless - it does exactly what it says it does; sheds weed. A great allround rudder that avoids the frustration of being stopped by clumps of sea grass.
Race - a standard size rudder that is very effective and works well with all ski designs.
Marathon - suited for flatwater racing and great to avoid those shallow obstacles (available for kayak, single skis and double skis)