Resin, some garden refuse and a boar knot. You won't get a handmade brush for cheaper than this, you get pretty and shiny as a bonus!
The brush stands 128 mm tall, with the loft at 52 mm. It has a waist of 20 mm and a belly of 35 mm. The brush weighs 76 grams and has a 20 mm Boar knot in it.