Silicone composition cross-linkable by polyaddition and comprising: ▪ at least two inter-reactive organosilica species, in the presence of a metal catalyst in order to allow cross-linking by polyaddition, these two species being constituted by polyorganosiloxanes; ▪ at least one cross-linking inhibitor, characterized in that → the species comprises at least one POS resin, having, per molecule, at least one C2-C6 alkenyl group bound to the silicon and comprising at least two different siloxy units chosen from those of formulae: W a Z b SiO (4-(a+b))/2 in which: - the symbols W, identical or different, each represent an alkenyl group; - the symbols Z, identical or different, each represent a non-hydrolyzable monovalent hydrocarbon group, without any adverse effect on the activity of the catalyst chosen from the alkyl groups as well as from the aryl groups, - a is 1 or 2, b is 0, 1 or 2 and a + b is comprised between 0 and 3, - optionally at least some of the other units are units of average formula: Z c SiO (4-C)/2 in which Z has the same meaning as above and c has a value comprised between 0 and 3; at least one of these two different siloxy units being a T or Q unit; → the species comprises at least one crosslinking agent POS having, per molecule, at least two hydrogen atoms bound to the silicon; → the molar ratio R = SiH/SiVi of the hydrogen species to the alkenyl species is such that R ≥ 2; → the concentration C B in species (in parts by weight for 100 parts by weight of) is such that 200 ≥ C B ≥ 30; and → the dynamic viscosity η (mPa.s at 25°C) of the composition before application is such that 2 ≤ η ≤ 500, the dynamic viscosity at 25°C being measured using a BROOKFIELD viscosimeter, according to the AFNOR NFT 76 102 standard of February 1972. ▪ at least two inter-reactive organosilica species, in the presence of a metal catalyst in order to allow cross-linking by polyaddition, these two species being constituted by polyorganosiloxanes; ▪ at least one cross-linking inhibitor, → the species comprises at least one POS resin, having, per molecule, at least one C2-C6 alkenyl group bound to the silicon and comprising at least two different siloxy units chosen from those of formulae: W a Z b SiO (4-(a+b))/2 in which: - the symbols W, identical or different, each represent an alkenyl group; - the symbols Z, identical or different, each represent a non-hydrolyzable monovalent hydrocarbon group, without any adverse effect on the activity of the catalyst chosen from the alkyl groups as well as from the aryl groups, - a is 1 or 2, b is 0, 1 or 2 and a + b is comprised between 0 and 3, - optionally at least some of the other units are units of average formula: Z c SiO (4-C)/2 in which Z has the same meaning as above and c has a value comprised between 0 and 3; at least one of these two different siloxy units being a T or Q unit; → the species comprises at least one crosslinking agent POS having, per molecule, at least two hydrogen atoms bound to the silicon; → the molar ratio R = SiH/SiVi of the hydrogen species to the alkenyl species is such that R ≥ 2; → the concentration C B in species (in parts by weight for 100 parts by weight of) is such that 200 ≥ C B ≥ 30; and → the dynamic viscosity η (mPa.s at 25°C) of the composition before application is such that 2 ≤ η ≤ 500, the dynamic viscosity at 25°C being measured using a BROOKFIELD viscosimeter, according to the AFNOR NFT 76 102 standard of February 1972. in which: - the symbols W, identical or different, each represent an alkenyl group; - the symbols Z, identical or different, each represent a non-hydrolyzable monovalent hydrocarbon group, without any adverse effect on the activity of the catalyst chosen from the alkyl groups as well as from the aryl groups, - a is 1 or 2, b is 0, 1 or 2 and a + b is comprised between 0 and 3, - optionally at least some of the other units are units of average formula: Z c SiO (4-C)/2 - the symbols W, identical or different, each represent an alkenyl group; - the symbols Z, identical or different, each represent a non-hydrolyzable monovalent hydrocarbon group, without any adverse effect on the activity of the catalyst chosen from the alkyl groups as well as from the aryl groups, - a is 1 or 2, b is 0, 1 or 2 and a + b is comprised between 0 and 3, - optionally at least some of the other units are units of average formula: Z c SiO (4-C)/2 in which Z has the same meaning as above and c has a value comprised between 0 and 3; at least one of these two different siloxy units being a T or Q unit; → the species comprises at least one crosslinking agent POS having, per molecule, at least two hydrogen atoms bound to the silicon; → the molar ratio R = SiH/SiVi of the hydrogen species to the alkenyl species is such that R ≥ 2; → the concentration C B in species (in parts by weight for 100 parts by weight of) is such that 200 ≥ C B ≥ 30; and → the dynamic viscosity η (mPa.s at 25°C) of the composition before application is such that 2 ≤ η ≤ 500, → the species comprises at least one crosslinking agent POS having, per molecule, at least two hydrogen atoms bound to the silicon; → the molar ratio R = SiH/SiVi of the hydrogen species to the alkenyl species is such that R ≥ 2; → the concentration C B in species (in parts by weight for 100 parts by weight of) is such that 200 ≥ C B ≥ 30; and → the dynamic viscosity η (mPa.s at 25°C) of the composition before application is such that 2 ≤ η ≤ 500, the dynamic viscosity at 25°C being measured using a BROOKFIELD viscosimeter, according to the AFNOR NFT 76 102 standard of February 1972.