DescriptionThis item is a set of professional piezo discs. Made from premium material, they are durable and practical for long time use. They are lightweight, easy to carry and install. Suitable for home appliance, watches, electronic toys, electronic drum triggers, acoustic transducers, etc.Features- Color: As Shown.- Material: Copper. - Size: About 2.50X2.50X0.10cm/0.98X0.98X0.04inch. - Adopted of premium material, it is both durable and practical. - Small, thin and lightweight. Low power consumption and high sensitivity. - Come with a large quantity to meet your need. - Easy to install in home appliance for sound and vibration detection. - Perfect for beginner to use as acoustic transducers, electronic drum triggers, buzzers, also used for watches, electronic toys, computer, etc.