The upper toilet tank switch fits the Twyford/Siamp Optima 49 flush valve button

Flush Button Compatibility with 49 Valves: This dual flush button, specifically designed for 49 valves, ensures seamless functionality with your existing system, providing efficient water usage and reliable performance. Toilet Push Button: With a 48mm diameter to fit standard tank holes (38-42mm), this toilet push button is easy to install. Simply screw it into the flush valve for a quick replacement. Toilet Tank ABS Material: Made from high-quality ABS material, this button offers durability and longevity, maintaining its elegant silver appearance while withstanding daily use. Dual Flush Operation: Featuring a dual flush capacity, this button is perfect for close-coupled tanks, allowing you to choose between a full or half flush to conserve water efficiently.