The Seoul Metropolitan 3000 series is a subway train built by Daewoo and Hanjin. Each car is 20 meters long and 3.18 meters wide. The maximum speed is 110km/h and has an electrical current of 1500 V DC. They were introduced on 1984 for Line 3 and Line 4 services. The Line 4 fleet was transferred to Line 3, and a variant was built for Line 2. The trains still operate on Line 3 on rush hour services, with the refurbished cars being scheduled to be scrapped on 2022.