Clamp-On Oarlock with standard 1/2" x 2" pin. Attaches quickly to oar shaft with easy to install bolted clamp. Fits oars between 3/4" and 1-7/16" in diameter. Recommended for freshwater use. Zinc plated steel construction. Sea-Dog Line is a 3rd generation family company with a history of satisfied customers stretching back to the company's start in 1933. The company is the recipient of multiple industry awards for quality and efficiency.