The McAlpine W1C is a 1 1/4" Backnut Slotted Washer designed for use with plastic basin wastes. It is a plumbing fitting that is used to provide a secure and leak-free connection between the basin waste and the basin itself. The Backnut Slotted Washer is constructed from high-quality plastic material that ensures reliable performance and durability. It meets all relevant plumbing standards and is suitable for a variety of applications, including domestic and commercial basin installations. The slotted design of the McAlpine W1C Backnut Washer allows for easy installation and removal of the basin waste, making it easy to clean and maintain. The backnut design ensures a secure and leak-free connection to the basin, preventing water from leaking out of the basin and causing damage to surrounding areas. Overall, the McAlpine W1C Backnut Slotted Washer is a reliable and efficient plumbing fitting that provides a secure and leak-free connection between the plastic basin waste and the basin itself. Its high-quality construction, slotted design, and backnut ensure easy installation, maintenance, and reliable performance. It is a valuable addition to any plumbing toolkit.