The TFV4 Mini sub ohm tank by Smok has a top fill design that is accessed through the slidding top making filling the tank easier. Designed with a 22mm base, the TFV4 Mini now sits flush with a wide range of mods. The double layered structure drip tip with airflow control provides a cooler vape for those with specific preferences. The double layered drip tip has also been improved on the inner layer of glass to avoid scalding. The tank also takes triple and quad coils with Japanese organic cotton wicking that is said to provide a more rich and smooth vape to the user. The tank is compatiable with all of the TFV4 coils.