It's clearly not N1251 as the denomination color is wrong. There are examples of N1251 and N1251.1 on the site. Problem is that all three of them are wrong.

The one marked N1251 should be N1251.1
The one marked N2311 should be N1251
The one marked N1251.1 should be N1294 (insert color is wrong but everything else matches so it could be the scan).