I can’t take all the credit. I have restored brushes before but this one in particular I bought the handle - it had already been drilled out. I filled the handle with epoxy (not the five minute kind) up to within a half inch of the top. I let it cure and then the next day installed the knot. It is a TGN 22mm Finest Badger Fan - Extra Hair set at a loft of 45mm. I like my brushes firm and this one I got just right. Don’t ask me how many I had to do to get the learning curve down! Ha, ha!