Among hairs from weasels' tail, under jaw,  and fore breast, which are widely used to produce wolf hair brushes, the tail parts are the best and usually for the high end product. Some low price wolf hair brushes are made from mount horse hairs, please read the retail. 
Wolf brushes are relative stiff. 
Some suggestion but not the definition depending on each user's habit and skills
Painting: Good for  Calligraphy and signature for painting, Bamboo, orchid, petals and strokes. Small/script size can be used for ribs of a leaf.
Branch in the method of double sketch/ bone style, such as plum tree. (雙鉤法畫梅幹）.Bill of bird. Stone, mountain, sketch in landscape.
Calligraphy: Good for Regular Script, Official Script 楷書，隸書

Wolf Hairs and other Hard Hairs

Wolf Weasel Hair Brush Detail Outline Script Gong Bi Sumi-e Painting Calligraphy
$6.89 - $19.99
$6.89 - $19.99
2pc- 24pieces Wolf Hair Brush Chinese Calligraphy Painting Ink Sumi
$6.99 - $95.99
$6.99 - $95.99
XL Badger Hairs 石獾 Brush Premium Calligraphy Painting Chinese Sumi-e Produce 斗笔
$37.99
$37.99
Weasel Tail Hair Red Sandalwood Shaft Produce Brush Fine Line Script Detail
$14.99
$14.99

Out of stock

On Sale

On Sale

Weasel Tail Hairs Rosewood Shaft Premium Brush
$27.99 - $79.99
$25.99 - $74.99

Out of stock

Weasel Wolf Hair Brush Chinese Japanese Calligraphy Painting Ink Sumi-e Water Color
$6.49 - $99.99
$6.49 - $99.99
No.1 Brand Shuangyang 雙羊 Wolf Hairs Brush
$16.99 - $38.99
$16.99 - $38.99
Rabbit Hair Chinese Hard Brush
$9.29 - $25.99
$9.29 - $25.99
No.1 Brand Shuangyang 雙羊 Fine Line Script Wolf Hairs Brush
$19.79
$19.79
Bear Hair Brush Professional Calligraphy Painting Chinese Sumi-e Produce
$23.99
$23.99
Wolf Weasel Horse Hair Brush Wood Shaft Calligraphy Painting Sumi-e Chinese Japanese
$11.69 - $27.99
$11.69 - $27.99

Out of stock

Weasel Tail Hairs Carved Solid Woods Shaft Brush Set /w Gift Box
$22.99 - $72.99
$22.99 - $72.99

On Sale

On Sale

Sumi-e Calligraphy Painting Brush Badger Hair Wood Shaft
$14.99 - $86.99
$9.99 - $86.99
Various Hairs Ebony Shaft Grape Eyeball Peony Brush
$22.99 - $69.99
$22.99 - $69.99
1pc XL Brush Jing Zha Wood Shaft Chinese Japanese Calligraphy Sumi-e
$32.99
$32.99
No.1 Brand Shuangyang 雙羊 Fine Line Script Rabbit Goat Mixed Hairs Brush
$17.49
$17.49
Sable Hair Chinese Hard Brush Bamboo Shaft
$20.50 - $62.99
$20.50 - $62.99