Curtain ring: outside diameter is approx. 37 mm/ 1.45 inch, dimension inside diameter is 30 mm/ 1.18 inch fit for less than 27 mm/ 1.1 inch curtain rods, please make sure the size when you buy it Quantity: totally 40 pack black metal curtain rings in the package, enough for daily life and replacement Installation: curtain ring go through the curtain rod one by one, and curtain hooks into the small ring, then you can try to sliding the curtain easily Good design: curtain rings are nice polished and surface without burrs, and black heavy duty metal curtain rings for your curtains, please be assured the application Wide application: the curtain rings are widely applied for most kinds of curtains, such as shower curtain, window curtain, french window curtain and so on; Please make sure the size before you buy it 40 Pack metal curtain rings hanging rings for curtains and rods, 30 mm internal diameter Heavy duty curtain ring: Make full use of the heavy duty metal and strict design, the bearing is good, and will not deform or drop out suddenly. Durable and wont rust: The black metal curtain ring are made of durable metal, nonporous surface and therefore will last for years without rusting. Eliminate scratch: Nice polished and smooth surface without burrs to catch on your curtain, eliminate snagging, tugging and pulling of the curtain. Widely apply: The curtain rings are in black, wide applied for most kinds of curtains, such as shower curtain, window curtain, french window curtain and so on. Please make sure the size: The internal diameter is 30 mm/ 1.18 inch fit for less than 27 mm/ 1.1 inch curtain rods, please make sure the size when you buy. Specifications: Size: Outside diameter: 3.7 cm/ 1.45 inches Inside diameter: 3.0 cm/ 1.18 inches Material: metal Color: black Quantity: 40 pack Package contents: 40 x Curtain rings