25:1 to 81:1 Baluns/Ununs These baluns and ununs can be used for impedance matching and also as End Fed halfwave antenna matching transformers to 50 or 75 ohm coax cable. Ferrite Core Products Store/Ferrite Core ProductsFerrite Rings, Beads & Snap OnsMix 31Mix 31Mix 43Mix 43Mix 52Mix 52Mix 61Mix 61Mix 75Mix 75All Ferrite Ring Toroid CoresAll Ferrite Ring Toroid CoresAll Snap On Split BeadsAll Snap On Split BeadsAll Slip On Ferrite BeadsAll Slip On Ferrite BeadsCombo Ring/Snap on/Slip on Packs - Mix 31, 61, 75 (.1-2000 MHz)Combo Ring/Snap on/Slip on Packs - Mix 31, 61, 75 (.1-2000 MHz)