Siamp Optima S Telescopic Dual WC Flush Valve

The Siamp Optima S is an adjustable dual flush valve for compatible ceramic or plastic WC cisterns. Its adjustment range helps match common replacement installations while the supplied actuation arrangement controls the flush from the cistern lid. Check the lid hole, outlet hole and cistern height before ordering.
| Brand | Siamp |
| Model | Optima S |
| Flush type | Dual flush |
| Flow rate | 3.5 l/s |
| Adjustable height | 282 to 432 mm |
| Lid hole size | 16 to 50 mm |
| Cistern outlet size | 58 to 72 mm |
| WRAS approved | Yes |
| NF certified | Yes |
| Manufacturer part no. | 32700410 |
| Pack quantity | 1 |
Measure cistern height and lid hole diameter, then set the telescopic overflow and lift rod to the height table in the manual before fitting. Hand-tighten the flush valve nut to the ceramic and add no more than a quarter turn — over-tightening damages the mechanism and is not covered by Siamp’s warranty. Maximum water level is 20 mm below the overflow. Fit the button to suit a 16 to 38 mm, 39 to 42 mm or 43 to 50 mm lid hole as shown in the manual. Use no limescale or chlorine cleaners in the cistern.
Specification sheet (PDF) · Installation manual (PDF) · See related WC cistern parts.