A 4-Inch Glass Cutting Disc Smt 111 Is A Specialized Tool Designed For Cutting Glass. The Disc Is Likely Coated With Diamond Particles, Which Provide Excellent Cutting Performance And Durability. The Smt 111 Model May Have A Specific Design Or Configuration Optimized For Cutting Glass. The Diamond-Coated Disc Enables Precise And Clean Cuts In Glass.