Uses Kings F Style D-Mount 1.25 Inch Diameter mounting hole. 75 Ohm Impedance. Ideally suited for outdoor use. Superior performance at up to 10,000 feet Alt. Gold over nickel center contacts. Durable brass housing plated with Kings TR-5 tarnish-resistant finish. Mechanical cable retention of 100+ Pounds. Operates to 2.5 GHz. Meets MIL-STD-202 environmental standards for thermal shock, moisture resistance, corrosion, vibration, and solvent resistance.