Abstract: An improvement in construction of a casing of a gas firing cooking apparatus which has elements, such as, a burner, control means for gas delivery to the burner, igniter, gas take-off head, etc., superposed on a removable gas cartridge and a surrounding casing with two chambers for separately receiving the superstructure and gas cartridge. An open end is provided at the bottom of the casing for easy access to the casing. A flexible springy member is disposed across the open end with one end thereof pivoted to the open end and other end thereof releasably fastened to the open end for clamping the gas cartridge against the gas take-off head to establish a gas-tight connection.