The VooPoo UForce U2 0.4 Ohm coils change the way you vape. Using a dual coil setup, they provide intense flavour and large vapour production. UForce N2 replacement coils feature a dual mesh coil setup and a resistance of 0.3 ohms. The dual mesh coils have an enlarged and faster heating area to provide a smooth flavour production and large vapour production.VooPoo UForce U4 coils use a quadruple coil setup, they provide intense flavour and large vapour production. The coils come in a handy pack of 5 and they have a resistance of 0.23 ohms which will change the way you vape.