The #7 Grinding Stone Refill 6‑Pack features Brownells’ top‑tier Premium Plus stones, engineered for serious metal‑finishing work. These points are made from uniformly sized aluminum oxide crystals enhanced with industrial‑grade cobalt, then bonded with cool‑running adhesives that deliver exceptional hardness, long service life, and fast, consistent cutting. They leave a smooth, ready‑to‑finish surface on both ferrous and non‑ferrous metals and resist loading, gouging, and premature wear. Each stone is mounted on a hardened, nickel‑plated steel shaft that stays straight and concentric even after repeated use. Brownells originally selected their ten most‑used point shapes for the full 30‑piece kit, and these economical 6‑Pack refills make it simple to keep your kit stocked and ready for any precision grinding task.