Transmission for vehicle

A transmission for a vehicle, comprising:

• a first input shaft continuously receiving torque from a power source and having a first input transfer gear thereon;
• a second input shaft selectively receiving torque from the power source through a clutch and having a second input transfer gear thereon;
• a coupling member allowing or restricting rotation of the first input transfer gear relative to the first input shaft, using a difference in rotational speed between the first input shaft and the first input transfer gear;
• a first countershaft and a second countershaft each having an output transfer gear to be engaged with the first input transfer gear and the second input transfer gear;
• and
• coupling devices selectively coupling the output transfer gears to corresponding countershafts and allowing torque from the power source to be transmitted to a desired shift gear by coupling output transfer gears connected to the desired shift gear in the output transfer gears to a corresponding countershaft in advance or after synchronization in shifting,
• wherein the coupling devices are disposed between the output transfer gears.