Males Red-backed Shrike have a grey head and a typical shrike black stripe through the eye.
Females and juveniles do not have the black eye mask of the male and are dull brown.
Juveniles are similar to females but differ by the scaly pattern on the mantle (back).

1st, 2nd & 3rd photo: A male. Sinoe area, Constanta County, Romania, 21 May 2018
4th photo: A male. Vadu area, Constanta County, Romania, 20 May 2018
5th photo: A female. Vadu area, Constanta County, Romania, 21 May 2018