Masked Lovebirds
Masked lovebirds are one of the "eyering" species. Below is a picture of a green Masked - the natural, or "wild" coloring.

Notice the wide, white ring around the eye. The head should have a solid black "hood" over it, with yellow around the neck, and a red beak. The flights are black.
A Blue Masked will have the eyering and black hood, but a blue body with white around the neck, and a pink beak.
I don't own any blue masked birds, but below (on the right) is a dilute masked, which is very similar. The diferences being that the dilute has more white on the head and body and white flights.

(The bird on the left is a wild-colored Fischer, and not as small as he appears. It is just the camera angle.)
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