Trigger dispenser head attachable to a container having an inner compartment for the containment of a liquid, comprising: a) a pressure chamber and a piston operable by a trigger and slidable in said pressure chamber in an active step in which it operates with pressure in the pressure chamber and in a return step in which it operates in suction in said pressure chamber; b) a mouth delimited by a mouth wall, in fluid communication with the pressure chamber through a passage, suitable for the passage of the liquid entering the pressure chamber during the return step and coming out of said pressure chamber during the active step; c) a dispenser duct, suitable for being placed in communication with the pressure chamber by means of said mouth, for dispensing the liquid outwards; d) valve dispenser means for controlling the exit of the liquid from the pressure chamber during the active step; e) a frame in which said pressure chamber is made and to which said valve dispenser means are attached; f) connection means separate from said valve dispenser means and suitable for mechanically connecting the valve dispenser means to the frame; wherein said frame comprises an annular connection wall about a container axis, radially externally spaced apart from the mouth wall, wherein the connection wall annularly delimits an intermediate compartment suitable to be placed in communication with passage through mouth and in communication with an intermediate duct, which connects said intermediate compartment with the dispenser duct; and wherein said valve dispenser means comprise a main body made of a flexible material and attached to the connection wall and to the mouth wall of the frame so as to delimit the intermediate compartment the main body comprising an annular membrane attached to the connection wall; and characterised in that, said connection means comprise an auxiliary body made of a stiff material compared to the material which constitutes the main body of the valve dispenser means, wherein the auxiliary body comprises a base and an annular coupling wall, which axially extends from the base, and wherein the coupling wall of the auxiliary body is snap-wise coupled with the connection wall of the frame. a) a pressure chamber and a piston operable by a trigger and slidable in said pressure chamber in an active step in which it operates with pressure in the pressure chamber and in a return step in which it operates in suction in said pressure chamber; b) a mouth delimited by a mouth wall, in fluid communication with the pressure chamber through a passage, suitable for the passage of the liquid entering the pressure chamber during the return step and coming out of said pressure chamber during the active step; c) a dispenser duct, suitable for being placed in communication with the pressure chamber by means of said mouth, for dispensing the liquid outwards; d) valve dispenser means for controlling the exit of the liquid from the pressure chamber during the active step; e) a frame in which said pressure chamber is made and to which said valve dispenser means are attached; f) connection means separate from said valve dispenser means and suitable for mechanically connecting the valve dispenser means to the frame; wherein said frame comprises an annular connection wall about a container axis, radially externally spaced apart from the mouth wall, wherein the connection wall annularly delimits an intermediate compartment suitable to be placed in communication with passage through mouth and in communication with an intermediate duct, which connects said intermediate compartment with the dispenser duct; and wherein said valve dispenser means comprise a main body made of a flexible material and attached to the connection wall and to the mouth wall of the frame so as to delimit the intermediate compartment the main body comprising an annular membrane attached to the connection wall; and characterised in that, said connection means comprise an auxiliary body made of a stiff material compared to the material which constitutes the main body of the valve dispenser means, wherein the auxiliary body comprises a base and an annular coupling wall, which axially extends from the base, and wherein the coupling wall of the auxiliary body is snap-wise coupled with the connection wall of the frame.