These Cataract SGG Oar Shafts have an internal counterbalance weight in the handle area. This offsets the weight of the blade and shaft past the oarlock for easy, low fatigue rowing. Shaft lengths are listed as the final length, which will include the approximately 27" long blade you choose (sold separately). For a list of ACTUAL shaft lengths, please see the Specs section. You don&';t have to know rocket science to row a boat, but it helps to have gear made by a company who does. Cataract shafts are made with the same filament wound glass/carbon/epoxy composite technology used by the aerospace industry. The SGG shaft, with its spiral wound fiberglass and carbon fiber lay up flexes and rebounds like a wooden oar without the maintenance issues of wood. The handle area has a four pound weight added. This counters the weight of the oar out past the oarlock. In a day&';s rowing, you lift that oar out of the water hundreds of times. This takes a lot of the work out of your outing! These shafts have an innovative feature. The end of the handle is notched. Placing your thumb in the notch lets you know the orientation of the blade without taking your eyes off the path ahead. Shaft comes with rope wrap and rubber stopper, for quiet rowing. Blades with 1 5/8" diameter shanks are sold separately so that you can choose the width and brand that best suits your needs. The removable blades also permit easy storage and transport.