Fire extinguishing device (100;200;300;400;500), the fire extinguishing device (100;200;300;400;500) comprises a flask engagement means (110;210;310;410;510), arranged to engage with a flask for compressed carbon dioxide and to hold the fire extinguishing device (100;200;300;400;500) in an operating orientation in relation to such a flask; which flask is associated with a longitudinal direction extending in a upwards direction from a bottom of the flask to a top of the flask and a downwards direction from said top to said bottom, a radial direction perpendicular to said longitudinal direction, and an angular direction; characterised in that the fire extinguishing device (100;200;300;400;500) further comprises a carbon dioxide directing means (130;230;330;430;530), arranged to direct a jet of carbon dioxide flowing out from the flask when said valve is open; and an actuating means (120;220;320;420;520), arranged to apply a pressure on said valve of said flask, which valve is spring-loaded towards a closed state of the flask, when said flask engagement means (110;210;310;410;510) is in said operating orientation so that the valve as a result of said pressure opens and carbon dioxide flows out from the flask, which actuating means (120;220;320;420;520) in turn comprises a rotary acting lever means for transferring a force applied by a user within said actuating means for applying said pressure, said rotary acting lever means being arranged to work by translating a substantially rotary motion of the rotary acting lever means, whereby a point on the rotary acting lever means at which the user applies said force travels a first distance in this rotary motion, into a corresponding travelled linear second distance of a valve actuator of the flask, said second distance being shorter than said first distance, and in that the flask is a flask for compressed carbon dioxide, which when completely filled contains between 0.4-0.5 kg of liquid phase CO 2 at between about 50 and about 250 bars of pressure. a flask engagement means (110;210;310;410;510), arranged to engage with a flask for compressed carbon dioxide and to hold the fire extinguishing device (100;200;300;400;500) in an operating orientation in relation to such a flask; which flask is associated with a longitudinal direction extending in a upwards direction from a bottom of the flask to a top of the flask and a downwards direction from said top to said bottom, a radial direction perpendicular to said longitudinal direction, and an angular direction; characterised in that the fire extinguishing device (100;200;300;400;500) further comprises a carbon dioxide directing means (130;230;330;430;530), arranged to direct a jet of carbon dioxide flowing out from the flask when said valve is open; and an actuating means (120;220;320;420;520), arranged to apply a pressure on said valve of said flask, which valve is spring-loaded towards a closed state of the flask, when said flask engagement means (110;210;310;410;510) is in said operating orientation so that the valve as a result of said pressure opens and carbon dioxide flows out from the flask, which actuating means (120;220;320;420;520) in turn comprises a rotary acting lever means for transferring a force applied by a user within said actuating means for applying said pressure, said rotary acting lever means being arranged to work by translating a substantially rotary motion of the rotary acting lever means, whereby a point on the rotary acting lever means at which the user applies said force travels a first distance in this rotary motion, into a corresponding travelled linear second distance of a valve actuator of the flask, said second distance being shorter than said first distance, and in that the flask is a flask for compressed carbon dioxide, which when completely filled contains between 0.4-0.5 kg of liquid phase CO 2 at between about 50 and about 250 bars of pressure.