The "Wooster 4″ Pro Classic Black China Bristle Wall Brush" is a paintbrush manufactured by Wooster Brush Company. Let us break down the name.
Wooster: Once again, this is the brand name, signifying that the product is manufactured by Wooster Brush Company.
The brush measures 4 inches wide. This breadth is ideal for covering larger areas rapidly.
Pro Classic: The term "Pro Classic" most likely refers to a brush in Wooster's professional-grade line. These brushes are engineered for great performance and longevity, making them ideal for both professional painters and discerning DIY enthusiasts.