Flushdaddy 1/2" Brass filling valve is a durable, professional-grade bottom-entry fill valve (model number T68) known for its longevity, ease of installation, and quiet operation. It's a popular choice among UK plumbers for both new installations and replacements of traditional ballcocks. 
Key Features
1/2-inch Brass Tail: The primary advantage is the robust brass shank, which prevents common issues like cross-threading during installation and offers superior durability compared to plastic alternatives.
"Twist N Click" Technology: This innovative design allows for washer changes in as little as 5 seconds, making future maintenance exceptionally fast and easy for professionals.
Adjustable Height: The valve is height-adjustable, typically ranging from 238mm to 343mm (approx. 9 to 13.5 inches), making it a universal fit for most cistern sizes and brands.
Water-Saving Delayed Fill: The mechanism is designed to delay the final refill of the cistern until the flush cycle is complete, saving water with every flush.
Encased Float: The float mechanism is shrouded or encased to prevent it from snagging on other cistern components, ensuring smooth and reliable operation.
Wide Pressure Range: It operates effectively across a broad spectrum of water pressures, from 0.13 bar up to 16 bar.
Quiet and Efficient: Users consistently report that the valve provides a quiet fill and a positive, absolute shut-off, eliminating annoying drips and constant running water.