The Black Widow RDA $30 Free Standard Post - has a turbine fan in the drip tip that pulls vapor off the coils and pushes it upwards to produce a denser vapor. It features a ceramic deck that helps dissipate heat and also prevent accidental shorts. The build deck features a two post design which enables you to easily build either dual or quad coil setups. The dual top airflow is fully adjustable and prevents leaking issues that affect most bottom or side airflow RDAs.