304 Stainless Steel Spring: The toilet button spring is made of high quality 304 stainless steel wire, It can withstand frequent use without losing its performance. Note: please check the size of your toilet tank lid hole before purchasing. our toilet button can compatible with most 48mm hole in the cistern lid dual flush toilet. Multiple Sizes: Our products are available in three different sizes, namely: 38mm, 48mm, 58mm, in order to avoid purchasing the wrong size product, please measure the size of the old toilet button before purchasing, and carefully check the size chart of our products before choosing the right size product to buy! Adjustable Twist Rod, Easy Installation: Installing the Owfeel toilet tank button is a breeze, Just follow these simple steps: 1. Unscrew the lock nut and insert the button into the hole (ensure the full-flush and half-flush buttons are aligned). 2. Check if the button rod makes proper contact with the button. If it's too long, trim it; if too short, twist the rod to extend it to the desired length(You extend the torque rod from 7 cm to 9.5 cm at most). Then tighten the lock nut. Advanced Plating Surface: The toilet buttons use advanced electroplating technology to give their surface a high gloss and ultra-smooth texture. Wear-resistant and corrosion-resistant, ensuring long-lasting durability even in humid bathroom environments. Note: Our toilet buttons are round and are only suitable for replacing round toilet buttons. To avoid choosing the wrong size, please measure the size of the toilet buttons in our measurement before purchasing. If you have any questions about this product, please contact us immediately.