Hamilton For The Trade Masonry Paint Brush 4" 3190201-40

The Hamilton Masonry Brush 4" (also called 100mm or 4-inch) is a professional-grade paintbrush designed specifically for applying masonry paints and exterior coatings on rough outdoor surfaces.

Key Features
Bristles/Filaments: Synthetic mix (often a blend designed for tough surfaces; some variants like the Performance line use natural & polyester mix). Provides good paint pick-up, excellent coverage, and durability on brickwork, render, concrete, and other masonry.
Ferrule: Rust-resistant stainless steel for longevity, especially important for exterior work.
Handle: Strong, comfortable beavertail or rounded shape for a good grip during extended use.
Size: 4 inches (100mm) wide — ideal for covering large areas quickly.

Best Uses
Masonry paints
Exterior emulsions and coatings
Rough surfaces like brick, blockwork, render, and concrete
Outdoor walls and large surfaces where speed and coverage matter

It’s part of Hamilton’s "For The Trade" range (professional line) and is praised for its spreading rate, making application faster than smaller brushes.

Advantages
High paint-holding capacity
Hard-wearing for tough jobs
Easy to clean (especially water-based masonry paints)
Good value for trade and serious DIY users

Hamilton also offers a Performance Masonry Brush variant, which emphasizes hard-wearing natural/polyester bristles for even faster application on exterior surfaces.
They're a go-to choice for painters and decorators working on exterior masonry projects.