A burner for use in a combustion chamber of a furnace or a forehearth, comprising - a gas delivery member for delivering a gaseous oxidant, - a fuel delivery member for delivering a fuel, and having a portion disposed at an interior of the gas delivery member and offset from a longitudinal axis of the gas delivery member, and - a flange assembly mechanically associated with the gas and fuel delivery members, the flange assembly adapted for rotational movement and comprising -- a first flange mounted to the gas delivery member, the first flange having a first plurality of holes therethrough, and -- a second flange fixed to the fuel delivery member for rotation therewith, the second flange having a second plurality of holes therethrough, -- the first plurality of holes in the first flange and the second plurality of holes in the second flange arranged for being in registration with each other upon rotational movement of the first and second flanges to a select position with respect to each other, and -- a fastener assembly to releasably secure the first and second flanges to each other at the select position to releasably secure the gas and fuel delivery members with respect to each other to provide a flame footprint at a select location in the combustion chamber, characterized in that the fuel delivery member is rotatable to circumscribe a path around a central longitudinal axis of the gas delivery member. - a gas delivery member for delivering a gaseous oxidant, - a fuel delivery member for delivering a fuel, and having a portion disposed at an interior of the gas delivery member and offset from a longitudinal axis of the gas delivery member, and - a flange assembly mechanically associated with the gas and fuel delivery members, the flange assembly adapted for rotational movement and comprising -- a first flange mounted to the gas delivery member, the first flange having a first plurality of holes therethrough, and -- a second flange fixed to the fuel delivery member for rotation therewith, the second flange having a second plurality of holes therethrough, -- the first plurality of holes in the first flange and the second plurality of holes in the second flange arranged for being in registration with each other upon rotational movement of the first and second flanges to a select position with respect to each other, and -- a fastener assembly to releasably secure the first and second flanges to each other at the select position to releasably secure the gas and fuel delivery members with respect to each other to provide a flame footprint at a select location in the combustion chamber, -- a first flange mounted to the gas delivery member, the first flange having a first plurality of holes therethrough, and -- a second flange fixed to the fuel delivery member for rotation therewith, the second flange having a second plurality of holes therethrough, -- the first plurality of holes in the first flange and the second plurality of holes in the second flange arranged for being in registration with each other upon rotational movement of the first and second flanges to a select position with respect to each other, and -- a fastener assembly to releasably secure the first and second flanges to each other at the select position to releasably secure the gas and fuel delivery members with respect to each other to provide a flame footprint at a select location in the combustion chamber,