Teclu burner

The Teclu burner is a laboratory gas burner, a variant of the Bunsen burner, named after the Romanian chemist Nicolae Teclu. It can produce a hotter flame than a Bunsen burner.
The lower part of its tube is conical, with a round screw nut below its base. The gap, set by the distance between the nut and the end of the tube, regulates the influx of the air in a way similar to the open slots of the Bunsen burner. The Teclu burner provides better mixing of air and fuel, which is what allows it to achieve higher flame temperatures than the Bunsen burner.