These types of steroids are generally made by non-licensed manufacturers and are not overseen by any regulatory board. Due to it becoming increasingly harder to obtain pharmaceutical grade steroids, most people opt for underground brands. The main problem with underground brands is no one knows what type of environment these steroids are produced in. They may or may not be produced in a sterile environment. There are however many big underground brands available that have hundreds of positive reviews, it is always best to stick with the big brands.