Before buying, please carefully review the description, pictures and check your computer model to make sure you are ordering the correct one. If you are not sure of your computer model, please confirm with us and send us your model and picture. Our a1707 internal subwoofer on the left and right sides with pre-installed adhesive for easy installation. Compatible P/N: MLH32LL/A* MLH42LL/A* MPTR2LL/A* MPTT2LL/A. Compatible with MacBook Pro 15 inch Retina A1707 Late 2016 to 2017 A1990 2018 2019 year. If your A1707 A1990 Speakers Left+Right Internal Speaker is faulty, cracked or broken so that it doesn't work properly, replacing this speaker is a good place to start.Once replaced, original high quality sound is restored.