The Studio Gear Blending Crease Brush #35 is made from squirrel hair and is super soft. The bristles are firm and dense, but they're also shorter and less wider compared to my Sonia Kashuk Large Crease brush (review). Therefore, the Studio Gear brush is more for smudging, adding color on the crease area and inner corner.
The length of the brush is 7.5 inches. It can be purchased for $30 at a Studio Gear counter in Macy's. If you have money to splurge, I would definitely recommend this brush.