Compatibility and fit: A single toilet flush button designed for doubleflush cisterns, compatible with SIAMPOPTIMA 49 valves. Suitable for water tank holes sized 1650 mm. Check your tank hole size before . Water saving dual flush: Full flush or half flush option to reduce water usage and lower utility bills without sacrificing flushing performance. Material and durability: Made from grade ABS, resistant to wear and moisture for lasting everyday bathroom use. Simple installation: Threaded installation that screws in easily with no special tools required. Instantly refreshes your toilet's look and improves flushing efficiency. Use scenarios: Replacing a worn or inefficient flush button on a doubleflush cistern in a home bathroom. Upgrading toilets in rental properties to improve water efficiency and reduce operating costs. installations in bathrooms with tank hole sizes of 1650 mm that require a reliable push button flush.