This porn video tag is a combination of three elements that describe the specific type of content in the video.
1. "Gay": The content of the video features men engaging in sexual activities with other men, specifically homosexual or gay sex acts.
2. "Black": The participants in this video are black or African-American men. This can refer to their race, ethnicity, or skin color.
3. "Men": The subject matter involves adult males (age 18 and over) participating in the sexual activities described.
So, the tag "gay-black-men" describes a video featuring gay sex acts between African-American men.