Yes, you can paint a polymer lower. There are a few things to keep in mind, though. First, you’ll want to make sure that the lower is clean and free of any oils or other contaminants. Second, you’ll need to use a high-quality primer designed for use with polymers. And finally, you’ll need to choose a paint that’s specifically designed for use with plastics or polymers. With the right preparation and materials, painting a polymer lower is possible.