Oumier Bulk RTA is a collaboration between Oumier and the YouTube Vape reviewer - VapnFagan.

It looks a beast with a 28mm diameter, the maximum capacity is 6.5ml.

The deck is a dual coil configuration with a postless design. You can adjust the airflow via the bottom airflow control ring and this feeds the air to the underside of the coils. And the top cap is a quarter turn unscrew to reveal the top refill ports. All in all, the Bulk RTA is worth a shot.