Thermoplastic composition comprising 30 - 90 wt.% of a semi-aromatic copolyamide prepared by direct solid-state polymerization, comprising repeat units derived from diamine and dicarboxylic acid, or salts thereof, or any mixtures thereof, wherein a. the diamine consists of 80 - 100 mole% of a mixture of tetramethylene diamine and hexamethylene diamine, and 0 - 20 mole % of one or more other diamine, relative to the total molar amount of diamines; wherein the diamine comprises tetramethylene diamine and hexamethylene diamine in a molar ratio in a range of 15:85 - 70:30; b. the dicarboxylic acid consists of 90 - 100 mole% terephthalic acid, 0 - 10 mole % of one or more other aromatic dicarboxylic acid and 0 - 2 mole% aliphatic dicarboxylic acid, relative to the total molar amount of dicarboxylic acids; c. the copolyamide comprises 0 - 2 mole % of repeat units derived from other monomeric components including 0 - 0.1 mole% of branching units, wherein the mole% is relative to the total molar amount of diamine, dicarboxylic acid and other monomeric components; d. the copolyamide has a viscosity number of at least 100 ml/g; measured by the method according to ISO 307, fourth edition, at 0.5 wt.% in sulphuric acid at 25 °C; and 10 - 70 wt.% of a reinforcing agent wherein the weight percentages (wt.%) are relative to the total weight of the composition. 30 - 90 wt.% of a semi-aromatic copolyamide prepared by direct solid-state polymerization, comprising repeat units derived from diamine and dicarboxylic acid, or salts thereof, or any mixtures thereof, wherein a. the diamine consists of 80 - 100 mole% of a mixture of tetramethylene diamine and hexamethylene diamine, and 0 - 20 mole % of one or more other diamine, relative to the total molar amount of diamines; wherein the diamine comprises tetramethylene diamine and hexamethylene diamine in a molar ratio in a range of 15:85 - 70:30; b. the dicarboxylic acid consists of 90 - 100 mole% terephthalic acid, 0 - 10 mole % of one or more other aromatic dicarboxylic acid and 0 - 2 mole% aliphatic dicarboxylic acid, relative to the total molar amount of dicarboxylic acids; c. the copolyamide comprises 0 - 2 mole % of repeat units derived from other monomeric components including 0 - 0.1 mole% of branching units, wherein the mole% is relative to the total molar amount of diamine, dicarboxylic acid and other monomeric components; d. the copolyamide has a viscosity number of at least 100 ml/g; measured by the method according to ISO 307, fourth edition, at 0.5 wt.% in sulphuric acid at 25 °C; and a. the diamine consists of 80 - 100 mole% of a mixture of tetramethylene diamine and hexamethylene diamine, and 0 - 20 mole % of one or more other diamine, relative to the total molar amount of diamines; wherein the diamine comprises tetramethylene diamine and hexamethylene diamine in a molar ratio in a range of 15:85 - 70:30; b. the dicarboxylic acid consists of 90 - 100 mole% terephthalic acid, 0 - 10 mole % of one or more other aromatic dicarboxylic acid and 0 - 2 mole% aliphatic dicarboxylic acid, relative to the total molar amount of dicarboxylic acids; c. the copolyamide comprises 0 - 2 mole % of repeat units derived from other monomeric components including 0 - 0.1 mole% of branching units, wherein the mole% is relative to the total molar amount of diamine, dicarboxylic acid and other monomeric components; d. the copolyamide has a viscosity number of at least 100 ml/g; measured by the method according to ISO 307, fourth edition, at 0.5 wt.% in sulphuric acid at 25 °C; and 10 - 70 wt.% of a reinforcing agent wherein the weight percentages (wt.%) are relative to the total weight of the composition.