This balun is a 49:1 balun for end-fed antennas. It only needs to be equipped with a 20-meter long vibrator (remember that it is a standard 20 meters) to naturally resonate in the four amateur bands of 7, 14, 21, and 28, and the height changes resonance The impact of the point is very small, which is very suitable for HAM with certain hands-on ability, the magnetic ring is fixed by PCB and works stably and reliably for a long time. Main parameters: 5-35MHZ standing wave less than 1.5 insertion loss less than 1.5DB withstand power 100W PEP (SSB) (baluns all passed the continuous emission test for up to 30 minutes, and the parameters are all real standards, we will never consider the standard 150W) color:As shown Material:Metal Package Contents: 1 x Shortwave Antenna Balun Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.