25 Piece 1/2" X 5/8" High Temp Silicone Rubber Tapered Plug Kit Powder Coating Custom Painting Supplies Bottom diameter: .512" - Top diameter: .669" - Length: 1.00" Flexible, durable and reusable. Withstands heat up to 600 degrees Fahrenheit/315 Celsius. Use for powder coating, painting, plating, anodizing, media blasting, etc. Premium quality silicone will not crack, shrink, harden or break.