Where does the kolinsky hair used in Kolinsky acrylic nail brushes come from? Our kolinsky hair is harvested from weasels during the winter months as the fur is thicker, fuller and healthier. Only the finest quality hair is selected in our 100% pure kolinsky acrylic nail brushes. Our kolinsky nail brushes are then assembled in Japan, Germany and the USA to ensure the finest balance of craftsmanship and performance. Best of all, our kolinsky acrylic brushes are available to you at a great value.