These basic oarlocks are excellent for recreational use in rivers with up to Class III ratings. Heavy-duty industrial-grade bronze-alloy ship screws are recycled to produce these strong oarlocks. The 5/8" diameter, 3-1/2" long shaft is precision-turned and drilled for a split ring. The horn opening is 1-5/8" with a 2-3/8" inside diameter. Oarlocks include Split Ring keepers. Sold individually or in pairs, so don't forget to order a spare. Oars with rope wraps or oar sleeves can sometimes fit snugly in oarlocks. Compare the measurements under the Specs tab to those of your oar shaft to ensure a good fit with these oarlocks. Industrial-grade bronze-alloy 3-1/2" long shaft 5/8" shaft diameter 1-5/8" horn opening 2-3/8" inside opening