The Michel Mercier Detangler Brush is amazing. It is used to brush through knots and tangles in the hair with greater comfort and relatively no pain at all. The difference between this brush and a regular brush is the different heights/levels of the combs on the brush head. An average hairbrush will have all the bristles/combs at just about the same height/length, whereas this detangling brush’s combs/bristles are at varied heights. This is exactly what detangles your hair and makes it pain free, without doing any unnecessary damage to the hair.
This is a great video to demonstrate how the brush works and what real people think.