central cylindrical body 8 and a mobile part 9 associated and cooperating with said body 8 and forming the nozzle the fixed part 7 of the device 3 comprises an outer body with radial fins 10 which support a cylindrical bush 11 having a frustoconical bottom 11a and a narrow top 11b and which support through their extensions 12 the central cylindrical body 8 coaxial and internal to said bush 11 as well as a wide upper flange 13 with bent edge 14 for connection to the mouth of the container 1 the central cylindrical body 8 of the fixed part 7 is crossed fig4 on its outer surface by seven cylindrical helical grooves 15 separated by an equal number of teeth 16 said helical grooves being inclined by about 20 u00b0 the mobile part 9 of the closing and delivery device 3 comprises a substantially cylindrical tubular element whose inner surface adheres for a short length 17 close to the cone shaped outlet end 18 to the central cylindrical body 8 of the fixed part 7 while for the remaining length 19 of said element the inner surface thereof keeps well apart from said body 8 creating a cylindrical cavity 20 the outer surface of said element 9 comprises in turn starting from the outlet end.