A screw cap lidded container for laboratory use comprising • a container body defining a chamber, • a tubular section of the container body that is connected at the rear to the chamber and has a container opening in the front, • an external thread on the outer periphery of the tubular section, • a circumferential first sealing surface on the tubular section, • at least one first projection (19, 20), which projects from the container body at a peripheral position of the tubular section, • a screw cap, • an internal thread on the inner periphery of the screw cap that can be screwed onto the external thread with thread play, • a circumferential second sealing surface on the screw cap, that by screwing the screw cap tightly onto the tubular section can be brought into sealing contact with the first sealing surface, and • at least one second projection (38, 39), which projects from the screw cap at a peripheral position of the screw cap, • wherein the first projection (19, 20) on the front side, in a circular cylindrical cut surface about the central axis of the tubular section, has an increasing shoulder, and/or the second projection (38, 39) on the back side, in a circular cylindrical cut surface about the central axis of the screw cap, has an increasing shoulder, wherein when screwing the screw cap tightly onto the tubular section, the first and second projections (19, 20; 38, 39) come into contact and glide onto each other with the at least one increasing shoulder, whereby a forward directed force is exerted on the screw cap, through which, in a ventilation setting in which a ventilation gap is present between the first and second sealing surfaces (22, 36), the internal thread is pressed with a flank against a thread flank of the external thread, the first and second projections are moved past each other during further screwing tightly and the first and second sealing surfaces (22, 36) attain a sealed setting in which they lie sealed against each other. • a container body defining a chamber, • a tubular section of the container body that is connected at the rear to the chamber and has a container opening in the front, • an external thread on the outer periphery of the tubular section, • a circumferential first sealing surface on the tubular section, • at least one first projection (19, 20), which projects from the container body at a peripheral position of the tubular section, • a screw cap, • an internal thread on the inner periphery of the screw cap that can be screwed onto the external thread with thread play, • a circumferential second sealing surface on the screw cap, that by screwing the screw cap tightly onto the tubular section can be brought into sealing contact with the first sealing surface, and • at least one second projection (38, 39), which projects from the screw cap at a peripheral position of the screw cap, • wherein the first projection (19, 20) on the front side, in a circular cylindrical cut surface about the central axis of the tubular section, has an increasing shoulder, and/or the second projection (38, 39) on the back side, in a circular cylindrical cut surface about the central axis of the screw cap, has an increasing shoulder, wherein when screwing the screw cap tightly onto the tubular section, the first and second projections (19, 20; 38, 39) come into contact and glide onto each other with the at least one increasing shoulder, whereby a forward directed force is exerted on the screw cap, through which, in a ventilation setting in which a ventilation gap is present between the first and second sealing surfaces (22, 36), the internal thread is pressed with a flank against a thread flank of the external thread, the first and second projections are moved past each other during further screwing tightly and the first and second sealing surfaces (22, 36) attain a sealed setting in which they lie sealed against each other.