This review is about the Tapered Blending Brush SS224, now also known as E40.
This is what the Sigma site says about this brush:
I can't tell you much else about this brush, except that it does exactly what it's made for, and I really like it. If you're looking for an affordable blending brush, and the Hema one doesn't do it for ya, this is the one to try!
It's not too expensive, and gives a great result.
It can be bought for 9 dollars at the Sigmastore. It comes in an eyekit with 6 other brushes which costs, for example, 39 euros at Enchantra.