HF Choke 160-6 meters Line Isolator Frequency: 1.8 - 300 MHz Applications include: Feeding dipoles, loops, or other similarly balanced antennas with unbalanced feedlines (coax). Reducing unwanted RF due to feedline proximity to antenna elements (low height dipoles, etc). Reducing man-made noise (computers, lamp dimmers, etc) conducted from the shack to the antenna by the feedline. Great for emergency "Go" kits when deploying less-than-optimal antenna installations (no counterpoises, poor grounding).