The present invention relates to a device for receiving and discharging a hardenable mass (2), preferably bone substitute and/or bone reinforcing material or bone cement or similar material, said device comprising a container (70) which is provided with a movable piston (86) for feeding the hardenable mass (2) out from a space (71) of the container, wherein a rear part (85) of the container (70) has a gas outlet (87) which is entirely or partly located in front of the piston (86) when said piston is situated in said rear part (85) and which gas outlet (87) permits gas present in the space (71) of the container (70) to flow out of said space (71) through said gas outlet (87) when said space is filled with hardenable mass (2).
