Common UK sizes
- Tap end: M10 or M8 male thread into the tap body (check your tap).
- Supply end: 15mm compression, or ½ inch female BSP nut with a washer.
- Lengths: 300mm and 500mm are common.
Where the seal is
Inside the female nut is a rubber washer. When you tighten the nut onto the valve or thread, the washer is squashed between the solid nut end and the solid fitting. That is your SSS seal. The threads only hold it together.
Pro tip: Look inside the nut before fitting. If the washer is missing, twisted or split, it will leak.
Fitting tips
- Screw the tap end in by hand only — do not over-tighten into the tap.
- Route the tail in a gentle curve; no sharp bends.
- Connect to an isolation valve so the tap can be isolated later.
- Tighten the nut by hand, then a quarter turn with a spanner.
- Test with full pressure.
When to replace flexi tails
- Rust or broken braiding.
- Bulges or kinks.
- Persistent weeping at the nut after a new washer.
- When replacing the tap — always use new tails.
