The SMOK TF Replaement Coil is specially designed for the Smok TF Tank. There are 2 different coil resistance for your selection. The 0.25ohm BF-Mesh Coil has honeycomb-shaped mesh inside, which provides extremely large heating area. So you can get excellent intense flavor with it. While the 0.5ohm ceramic coil is a kind of durable coil for intense vaping flavor.