The 681-2000 series prototypes were owned by Hokuetsu Express, used exclusively on the Hakutaka services between Kanazawa and Echigo-Yuzawa between 1997 and 2015. Two 6-car and two 3-car sets were produced (N01, N02; N11, N12). These sets, along with the JR West 681-0 series “White Wing” sets, are able to achieve the speed of 160km/h on the Hokuhoku Line portion of the service.
The 681-2000 series differ from the 681-0 series by their livery – the former has a crimson red front and accent line on the sides while the JR West ones have a grey front and blue line on the sides.
The 681 and 681-2000 series and its successor 683-8000 series still hold the record for the fastest track speed on narrow-gauge tracks in Japan.
Model Specifications
| Manufacturer | Kato |
| Product code(s) | 10-381 |
| No. of cars | 9 |
| Additional notes | No additional notes. |