The blue 30 ppi brush have a "rougher" surface than the black and white brushes. It is "airier" in the structure and functioning well even in humidity when it releases liquid and dry faster. It is also a bit more rigid structure than the black brushes. Throughout hole so you can use both ends. The blue brushes that come with Taksopen / The Roofbrush are our "all-round" brushes and fit most roof types (not roofing felt) and especially good for the lighter clay tiles so that you do not bump into them too hard and risk that they are moved (so you have to go up on the roof and fix them..).
Also available in black, Item No. TB15.