5.99-inch (2160×1080) display, Snapdragon 660 (4×2.1GHz + 4×1.8GHz), 4GB RAM, 20MP front facing camera, 20MP+12MP rear camera, fingerprint sensor, 32GB memory, 3000mAh battery, 158.7×75.4×7.3mm, Android One, 168g.
Early Xiaomi Mi A2 listing reveals official press renders and full specs
UPDATED BY MODERATOR WITH FULL SIZE RENDERS (THANK YOU ZYAD)