DC resistance 2x50 = 100 Ohm. See also DLR-2 and DLR-5 as balanced armature phone. See also the article for DLR-5 about rewinding. There are some other brands and US made balanced armature type headphones like the US Navy WWII (WW2) Deck Talker Headset Type R17T23.
Portovrij? In NL boven € 200,-