Blue
A variant of Quaker parrot (monk parakeet) (Myiopsitta monachus)

Representative Quaker parrot (monk parakeet)photo — a dedicated image of this exact morph isn't available yet.
A recessive color mutation replacing green with powder-blue while keeping the grey breast. The most popular Quaker mutation.
Keeper tips for this variant
Blue is the original Quaker mutation and carries no health issues, but as a recessive trait both parents must carry it — pairing untested birds gives unpredictable results.