The size of the swallow is slightly smaller than the sparrow. The body length of an adult individual is 12–17 cm, with a mass of 18–19 g. Like all members of the family, it is characterized by a fragile physique: the body is elongated, the head is slightly flattened, and the beak is small. The tail has a small neckline, the wings are narrow and long. Wingspan is from 20 to 33 cm.
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