The Ehpro Armor Prime Mech MOD is constructed with high quality brass. It is compatible with a single 20700, 21700 and 18650 battery. The Ehpro Armor supports a minimum coil resistance of 0.15ohm. The chipset in Armor Prime provides various protections for a safe vaping too. The LED indicator shows battery life clearly. The Ehpro Armor Prime Mech MOD is definitely an ideal choice for cloud chasers.