You build this kit to feed your EFHW (End Fed Half wave) or EFRW (End Fed random Wire) antenna depending on how you build it (instructions for both ways build in manual). This is the KM4CFT 20 WATT End Fed QRP unun kit, very small (1 7/8"L x 5/8"W and very light (0.6 ounce)! ).
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