Clearomizer:
Clearomizers or "clearos", not unlike cartotanks, use a clear tank in which an atomizer is inserted. Unlike cartotanks, however, no poly-foam material can be found in them. There are a lot of different wicking systems employed inside of clearomizers to ensure good moistening of the wick without flooding the coil. Some rely on to bring the e-liquid to the wick and coil assembly (bottom coil clearomizers for example) whereas others rely on capillary action and to some degree the user agitating the e-liquid while handling the clearomizer (top coil clearomizers). The coil and wicks are typically inside a prefabricated assembly or "head" that is replaceable by the user and can contain either single or dual coils. Present day clearomizers commonly have adjustable air flow control. They also hold up to 5ml of e-liquid. Tanks can be either plastic or glass. Some flavours of e-juice have been known to crack plastic clearomizer tanks