Finland.

White ring with a black three alpha code (on one leg) and metal ring (on other leg).

note 1 : Up to 2014 a total of 3 rings delivered 2013.

note 2 :

White ring with a black two alpha-numeric code (on right tarsus).

note 1 :  

Yellow ring with a black three alpha code (on one leg) and metalr ring (on other leg).

note 1 : 

White ring with a black two alpha code (starting letter 'F').

note 1 : up to 2014 total 17 rings delivered 2008.

note 2 :

Yellow ring with a black three alpha code.

note 1 : used codes are Cxx, Fxx, Jxx, Kxx, Lxx, Uxx and Vxx. and for the year 2015-2020 : Mxx, Nxx, Uxx, Pxx, Sxx, Txx.

note 2 : up to 2014, a total of 730 rings were delivered since 2008-2014.

note 3 :  in 2022 we have planned to take also codes Wxx, Xxx, Yxx and Zxx into use as well as also alpha-numeric rings starting with letters C and F (A is already in use in another project and letters not used are : B, D and E.
Also combinations of numbers/letters in all possible orders, i.e. "C/letter/number", "C/number/letter", "C/number/number"  & the same for F.
See project : https://cr-birding.org/node/6042

note 4 :

White ring with a black 3 alpha code, starting letter C'.

note 1 :

Orange ring with black five alpha-numeric code : starting letter 'C' and xxxx (where x is a number or letter).

note 1 :

Red ring with white five alpha-numeric code : starting letter 'C' and xxxx (where x is a number or letter).

note 1 :

White ring with black five alpha-numeric code : starting letter 'C' and xxxx (where x is a number or letter).

note 1 :

Yellow ring with black five alpha-numeric code,  starting letter 'C'.

note 1 : up to 2014, a total of 16 rings were delivered since 2009

note 2 : there can exist small check marks in the code (like dots between characters), inform them also.

note 3 :