These are whistle kettle cover knobs, which are manufactured with PP material, practical and durable enough to use. Whistling design, the sound is clear and not harsh. It is compact and easy to install, which is the great choice for you, convenient for you to add and pour water. Features -Color:As Shown-Material:PP -Size:5.50X5.50X3.60cm/2.16X2.16X1.41in- Manufactured by PP material, safe and reusable. They are simple and convenient. Easy to remove and simple to install, simple but practical, they are great kitchen gadgets for bringing much convenience to you. - They will make a loud whistle to ensure that you can hear it when the water boils.- Suitable for most whistling kettles cover, which ensure its practicality and popularity.- The kettle cover knob is easy to use and install, suitable for home teapot and water kettle.- Fine workmanship, durable and sturdy, not easy to wear or tear, you can use it with confidence.Packing list: 2 whistling kettle pan lid knobs