Extension (1) for increasing of the upper limit of application of polyurethan foam from a dose (2) including a connection socket (3) connected with a swinging controller (4) where on the connection socket a lower bending (5) is connected, on which a tube prolongation (6) is connected, on which an upper bending (7) is connected and on it an application ending (8) is connected, where the extension (1) is provided inside with a freely arranged wire (10) for its shaping and the connection socket (3) is provided with at least one hole (13) and simultaneously there is a hook (14) in the end of the wire (10), diameter of which is smaller then the diameter of the hole (13) for inserting of the hook (14) into the connection socket (3) and both over the wire (10) and over the connection socket (3) the tube (11) is pulled over up to the foot (17) of the connection socket (3).