Most of these products are from the testosterone manufacturer's site. There are many other testosterone supplements that have different ingredients. If a product I am reviewing does not have these, I don't believe that it is very good. However, if it is good, I recommend you try it. I don't have any relationship with any of the companies listed here. All of the products are from companies with excellent safety records.
The most important thing to know about testosterone is that you need to know the right dosage for you. Most men will take anywhere from 30 to 40 micrograms per day. There are a lot of different products, so check the labels for dosages. One thing you should know is that the body needs to metabolize testosterone in order to reach its peak levels. Most guys will be able to tolerate a small amount of testosterone, but it may take a while to reach your maximum levels. Testosterone supplements can help increase testosterone levels for a while, but it will eventually decrease them. Once you start taking testosterone supplements, the first time you start you should stop and check your blood pressure. If your blood pressure is high, then you should cut down your dose of testosterone.