Those are the prebuilt coils
for rebuildable dripping atomizers and rebuildable atomizers.
The coils are made of Kanthal and Nickel 200, with a diameter of 0.3mm, 0.4mm
They are twisted, so as to reduce the resistance of the coil but still maintain a high coverage on the wick.
Only use the Nickel coils when using a temperature limiting mod, like Hcigar HB DNA 40W Box Mod or Smok M80 Plus
Do NOT use Nickel coils on ANY mod other than those with temperature limiting.