Black Metal Curtain Ring Pack - Extendable Pole Rings x6 Matt Black To Fit 25 - 34 mm Curtain Pole (Will fit curtain poles up to 35mm Diameter). Classic black metal curtain rings, suitable for a variety of metal curtain poles for doors and windows. Pack Of 6 Smooth Gliding Rings Attach Curtain Hooks To The Eyelet & Curtains (Not Included) Inner Diameter: 38mm Outer Diameter: 50mm Easy to install curtain rings, simply slide the curtain rings on to curtain rods or poles, one by one. Then use curtain hooks (not provided) into the small rings of these metal curtain rings to hang the curtains and then you can slide the curtain easily onto the curtain rod or pole. Suitable for most curtain poles and rods of 25 - 34 mm diameter - Curtain Rings ideal for use with iron curtain poles and rods. Especially designed for use with extendable poles. Suitable for curtain poles as the curtain rings are rust resistant. The curtain rings are made of a sturdy rustproof metal, making the curtain rings strong and not easily deformed by any curtain hanging from the rings and provides a smooth running surface to slide the curtain easily. As the rings will not rust easily making them ideal for shower curtains.