Our round classic cupboard door knob is 30mm in diameter and are made from solid brass materials. The knobs are strong and heavy and will not tarnish over time. They are ideal for built-in cupboards and drawers, side tables and vanities. They have a classic appeal to them and are available in brass or shiny chrome. Screws included. Please ensure to clean the classic cupboard door knobs with a dry cloth and not use any chemicals as they have a clear lacquer to protect them.