The McAlpine S/GRID-25CB-CP Sink Overflow Grid Cover is a chrome-plated plastic overflow grid designed to fit into your sink overflow. The S/Grid-25Cb-Cp Sink Grid is made from durable plastic that is resistant to rust and corrosion, ensuring it will last for years to come. It is also plated with chrome, which gives it an attractive and shiny appearance that is easy to clean. One of the key features of the McAlpine Sink Overflow Grid Cover S/Grid-25Cb-Cp is the integrated stay to connect a chain/plug to. It is designed to fit a variety of sinks, making it a great choice for homeowners with different types of sinks. The grid is also easy to install and remove, making it a convenient and practical accessory for any kitchen. Overall, the McAlpine Sink Overflow Grid Cover S/Grid-25Cb-Cp is a reliable and durable accessory for protecting your sink overflow from damage. Its high-quality plastic construction and chrome-plated finish make it a stylish and practical addition to any kitchen.The item has an outside diameter of 40mm. The thread diameter is 27mm and the length of the thread is also 27mm.