This replacement diaphragm is designed for the speaker EAW J560 or J560e , which is compatible with 8 Ohm amplifiers. and  is a 3" size (74.5mm). It is a high-quality replacement part for your speaker, ensuring optimal performance and longevity. The unit quantity is one, and it is a type of diaphragm driver. This item is perfect for those looking to replace their old or damaged diaphragm in their EAW J560 speaker. I bought it awhile ago. Never used.