SeaLux 316 Stainless Steel Clamp-On Oar Lock 1/2"x 2" shaft one pair SeaLux SS Steelhead Clamp-On Oarlocks fit all popular oar sizes Feature Marine Grade 316 stainless steel construction that resists rust. The Clamp-On Oarlock fastens securely to the oar with one adjustable bolt with no drilling required. Easy-to-install oarlocks Replace worn-out oarlocks ;Inner Diameter: 1-3/8" to 1-3/4"; Shaft 1/2" For Fresh or Salt Water