Fully tested and 100% functional. Feel free to send us a message with your S/N and we can check compatibility for you. IMac19,1 Retina 5K 2019: EMC 3194 - MRR02LL/A (3.1 GHz Core i5). High quality packaging to ensure you'll receive your item safely.Please select the correct reason for return. A tamper-proof sticker will be on the item, keep it there, you'll need it in case of return. The item must be in the same condition as you received it. Please pack the item safely, to make sure it will arrive not damaged.