Baluns by LDG, suitable for use with LDG tuners or stand alone. Power load max. 200 W, one side has a PL socket, the other side two binding posts for connection to wires or ladder lines (twin lead). The baluns are made for outdoor use, for permanent outdoor installation they should be waterproofed with an additional silicone sealing at the back of the enclosure.The 4:1 balun is a voltage-type balun and is typically used for longwire antennas (length > lambda/2), but also for Windom and other dipole antennas. Usually the balun is placed directly at the antenna, not indoors behind the tuner. The 1:1 model is a current balun which also serves as an HF choke. It is typically used as a transition from coaxial cable to ladder line.The 4:1 Unun is typically used with very long, high impedance wire antennas and loops, usually it must be used with a tuner. Weight approx. 170 g, size 128 x 64 x 32 mm, 200 W max.