Multifunctional precision grinding heads (0.3MM/0.4MM/0.5MM) for micro-soldering tasks on PCB boards and smartphone components. High-grade tungsten steel tips maintain sharpness through prolonged use with heat-resistant nickel plating. Ergonomic anti-slip handles enable millimeter-level control during delicate circuit board repairs. Three interchangeable sizes cover SMD component rework, BGA chip maintenance, and connector pin restoration. Diamond-cut edges ensure clean solder joint removal without damaging surrounding circuits. Professional-grade set meets industrial standards for mobile repair shops and electronics manufacturing lines. Vacuum-sealed packaging prevents oxidation for out-of-box readiness. Works with all standard rotary tools (15,000-40,000 RPM compatible).