Origin and use neighborhood of Boom near Antwerp, where many bleach-works were established and the dogs were used to guard the fields where costly linen was put out to bleach.
- Appearance similar to that of the Groenendael, except for the color, which should be fawn with blackening on the muzzle and tail.
- And the coat, which should be rough harsh, shaggy, and 2 inches (6cm) long, except on the head, which is short-haired.
- 2 Height at withers: dog, about 24 inches (62 cm), bitch about 23 inches (58 cm).
- Color own with aces of black on the muzzle.