Reinforced thermoplastic polymer composition, consisting of: polymer comprising at least a first semi-crystalline semi-aromatic polyamide (SSPA-1); 10 - 70 wt.% of at least one reinforcing agent, and 0 - 25 wt.% of one or more other components, wherein the SSPA-1 - is present in an amount in the range of 30 - 90 wt.%; - has a melting temperature (Tm) of at least 300 °C; and - consists of: (A-1-a) 90 - 100 mole% of repeat units derived from (i) aromatic dicarboxylic acid and (ii) diamines, and (A-1-b) 0 - 10 mole% of repeat units derived from other monomers; - and the diamines (ii) consist of 80 - 95 mole% of linear aliphatic diamine, 5 - 20 mole% of 2-methyl-pentamethylene diamine, and 0 - 10 mole% of other diamines; and wherein - the mole percentages (mole%) of the diamines are relative to the total molar amount of diamines; - the mole% of (A-1-a) is based on the combined molar amount of the aromatic dicarboxylic acid (i) and the diamines (ii); - the mole% of (A-1-a) and (A-1-b) are relative to the total molar amount of monomeric repeat units (A-1-a) and (A1-b) in the SSPA-1; - the weight percentages (wt.%) of components, and and of the SSPA-1 are relative to the total weight of the composition, while the sum of, and is 100 wt.%. polymer comprising at least a first semi-crystalline semi-aromatic polyamide (SSPA-1); 10 - 70 wt.% of at least one reinforcing agent, and 0 - 25 wt.% of one or more other components, wherein the SSPA-1 - is present in an amount in the range of 30 - 90 wt.%; - has a melting temperature (Tm) of at least 300 °C; and - consists of: (A-1-a) 90 - 100 mole% of repeat units derived from (i) aromatic dicarboxylic acid and (ii) diamines, and (A-1-b) 0 - 10 mole% of repeat units derived from other monomers; - and the diamines (ii) consist of 80 - 95 mole% of linear aliphatic diamine, 5 - 20 mole% of 2-methyl-pentamethylene diamine, and 0 - 10 mole% of other diamines; and wherein - the mole percentages (mole%) of the diamines are relative to the total molar amount of diamines; - the mole% of (A-1-a) is based on the combined molar amount of the aromatic dicarboxylic acid (i) and the diamines (ii); - the mole% of (A-1-a) and (A-1-b) are relative to the total molar amount of monomeric repeat units (A-1-a) and (A1-b) in the SSPA-1; - the weight percentages (wt.%) of components, and and of the SSPA-1 are relative to the total weight of the composition, while the sum of, and is 100 wt.%. - is present in an amount in the range of 30 - 90 wt.%; - has a melting temperature (Tm) of at least 300 °C; and - consists of: (A-1-a) 90 - 100 mole% of repeat units derived from (i) aromatic dicarboxylic acid and (ii) diamines, and (A-1-b) 0 - 10 mole% of repeat units derived from other monomers; (A-1-a) 90 - 100 mole% of repeat units derived from (i) aromatic dicarboxylic acid and (ii) diamines, and (A-1-b) 0 - 10 mole% of repeat units derived from other monomers; - and the diamines (ii) consist of 80 - 95 mole% of linear aliphatic diamine, 5 - 20 mole% of 2-methyl-pentamethylene diamine, and 0 - 10 mole% of other diamines; - the mole percentages (mole%) of the diamines are relative to the total molar amount of diamines; - the mole% of (A-1-a) is based on the combined molar amount of the aromatic dicarboxylic acid (i) and the diamines (ii); - the mole% of (A-1-a) and (A-1-b) are relative to the total molar amount of monomeric repeat units (A-1-a) and (A1-b) in the SSPA-1; - the weight percentages (wt.%) of components, and and of the SSPA-1 are relative to the total weight of the composition, while the sum of, and is 100 wt.%.