Adapter cords adapt from one type of plug to another, but do not change the impedence of the earphones or microphone.
Choosing your cord:
Description starts with the jack(s) on the helmet side and ends with the plug(s) on the radio side.
TP-120 is single plug or Jack(U-92)
P5568 is two plug General aviation plugs or jacks
U-75 is a single plug with two positioning pins, O2 Jack (U-61).
Available in 12", 36", 48", and 60"; or call for custom lengths.
Call for custom plugs or jacks.