1It is made of high quality metal material, strong and durable. 2It can adjust the received signal by switching the antenna, convenient and practical. 3The interface with the antenna is made by precise technology, and there is no problem of bad contact. 4It can be connected to three antennas, outstanding performance. 5The impedance is only 50 ohms and the loss is very low.Features: It is made of high quality metal material, strong and durable. It can adjust the received signal by switching the antenna, convenient and practical. The interface with the antenna is made by precise technology, and there is no problemof bad contact. It can be connected to three antennas, outstanding performance. The impedance is only 50 ohms and the loss is very low. Specifications: Material: Metal Size: Approx. 9.5*7.7*2.9cm/3.74*3.03*1.14inch Frequency: DC-800MHz 2 Position Switch 1-Input -3-Outputs Insertion loss: less than 0.1dB (DC-500MHz), more than 0.15dB (500-1000MHz) Isolation: more than 60dB (DC-500MHz), over 50dB (500-800MHz) VSWR: less than 1.1 (DC-500MHz), less than 1.2 (500-1000MHz) Through power: (less than SWR1.2), 1.5KW (DC-30MHz), 1KW (30-150MHz), 500W (150-800MHz) Impedance: 50 Ohm Interface: M-J Interface Package list: 1 x Switcher 2 x Screw Note:Please note that CX-310 and CO-301 are the same product, and make sure you will not mind before ordering.