Specification:

100% new and high quality
Material: Rubber
Colour black
Compatible Model: for Macbook Pro Retina A1398 A1425 A1502

How to use:
Remove the bottom case and wipe the dropped stitch with a dry cloth to remove the dust, but not wet.
Heat the dropped stitch with a blow dryer, when it is hotted, stick on the rubber foot directly.
On until it is cooling, then tighten the bottom case, toast the cylinder with a lighter, after dissolving, quickly press to let it stuck in the bottom case.