The NRS Convertible Oar Right keeps your oar blade in the right position for full power strokes. The spline of the NRS Convertible Oar Right fits between the horns of an open oarlock to lock your oar blade in position for the most effective stroke. You can still feather the oar blade by simply tugging the oar in so the spline of the NRS Convertible Oar Right clears the oarlock horns or you can flip the spline up and out of the way for easy feathering. For Carlisle and Cataract oars, use the Molded Oar Sleeve (sold separately) with the NRS Convertible Oar Right for proper fit. Adjusts from 2 in to 2 1/4 in (Carlisle & Cataraft Oars with Oar Sleeve). Sold individually.