1. Reverse Recovery Time (trr): The 1N4002G-T is specified at 2 µs, whereas the 1N4002L is only marked as ">500 ns." The G-T variant offers clearer switching characteristics. While this difference has no practical impact in low-frequency switching or line-frequency rectification applications, it indicates tighter manufacturing process control and more rigorous parameter specification for the G-T part. 2. Junction Capacitance: The 1N4002G-T has a junction capacitance of 8 pF, compared to 15 pF for the 1N4002L. The lower junction capacitance reduces parasitic effects at higher frequencies. Although both diodes are not fast-recovery types, the G-T version is slightly less susceptible to high-frequency noise in the circuit. 3. Junction Temperature Range: The 1N4002G-T is rated for -65°C to 175°C, while the 1N4002L is rated for -55°C to 125°C. The G-T version offers a wider operating temperature range, with a 50°C higher maximum junction temperature. This directly translates to higher reliability and longer operational life in high-temperature environments, likely due to improved die technology or packaging materials. In summary, while sharing identical core electrical parameters, the 1N4002G-T offers enhancements in high-temperature reliability and high-frequency parasitic characteristics, making it a direct upgrade and replacement for the 1N4002L.