The porn video tag "for-sale" refers to a scene or content where the individuals involved are engaging in sexual activities specifically for the purpose of selling it as adult material. This could include scenes from professional adult films, amateur homemade videos, or even live cam performances. In this context, the term "for-sale" highlights that the act of sex is being recorded and/or performed with the intent to be sold and viewed by others, rather than being a private or personal experience.