5 cm in diameter around the black seal. Screw of the first ( about 8 mm holes insert). Black rubber screw length: 2 cm the left and right. For old school sink strainer. Specially for Kitchen Basin colour:Silver Material:stainless metallic Size: 7 cm diameter Package Contents: 1 x kitchen sink strainer Only the above package content, diversified products will not be included. Note: Light and various exhibits may cause the colour of the thing in the picture slightly assorted from the genuine thing. The measurement allowed error is +/- 1-3cm.