This clamp mount is made for side mast or vertical rail mounting of the base of dual base antennas. It is ideal to use for the AC Antennas antenna base e.g. the CX4 antenna series. N245F is a stainless steel (SS304) mount thus withstanding long term rough weather conditions at sea. It measures Ø31-Ø60mm/ 1 1/4"-2 3/4" in rail diameter and is 220mm long. This mount is manufactured in premium quality materials in order to prevent galvanic corrosion. The mount is always subject for improvement. The mount has the same rugged design as all other AC Antennas products thus it withstands harsh environmental conditions, both on Sea and Land.