I used my new Thater brush for the first time today and was very pleased with it. It's a 4125/2 two band 26 mm bulb knot. I've been searching for a brush with the backbone I want with nice soft tips. All I can say it this brush delivered. I've been experimenting with boar and synthetics, and decided to give the Thater a try, time will tell but so far I really like this brush. Maybe not quite as soft as my Simpsons Chubbies, but definitely more backbone!