Upgrade your grinding and cleaning tasks with this 12 - pack wire brush set. The brushes are made of premium carbon steel, compatible with 4 1/2 angle grinders and feature a 5/8 - 11 thread arbor hole. With a MAX RPM of 12,500, they offer high - performance and durability. The set includes 4 in. and 3 in. wire wheel and cup brushes in both knotted and coarse crimped designs. The wire wheel brushes can be used horizontally or vertically, suitable for light to medium - duty jobs on irregular surfaces. The wire cup brushes, fixed to a solid ring, reduce vibration for smoother operation. These brushes are perfect for weld cleaning, general cleaning, deburring, and removing rust and other debris. Whether you're working on large surfaces or small workpieces, this set provides a comprehensive solution for all your grinding and cleaning needs.