The Chaffinch's large double white wing bars, white tail edges and greenish rump easily identify this 14–16 cm long species. The breeding male is unmistakable, with his reddish underparts and a blue-grey cap. The female is drabber and greener, but still obvious.
Although rather common in the Netherlands I've added the chaffinch to the NWF mission. For me it's an EXTRA-ordinary bird, the singing of the chaffinch is a sign of the beginning of spring.