Need help Identifying Byzanthine or what is ?

[Sasa]

I have this coin, but what is ?

[Vladimir]

Hello!
This is Anonymous Byzantine follis class A JESUS CHRIST
Attributed to the reign of John I.
Obv.: Bust of Christ, facing, Wearing nimbus and holding book with Gospels.
Rev.: Legend in four lines.
Depending of the weight it van be A1(7-8 grams), A2(15-20 grams), or A3 (9-10 grams).
Hope this will help.

[Sasa]

Thanks Vladimir.
P.S It is rare or ?