Testosterone Suspension is an injectable testosterone hormone in a water base that was developed and used for decades, and is actually the first anabolic androgenic steroid made. For the purpose of building mass, Testosterone Suspension has never been surpassed since it was first developed in the 1930s.
This product is suspended in propylene glycol or oil as well (which makes for a very painful injection). It has no ester attached; therefore no ester is calculated into the weight. This is extremely beneficial to the user since 100mg of Testosterone Suspension will yield 100mg of testosterone unlike the other esterfied testosterones such as (for example) Testosterone Enanthate, which only yields 72mg of actual testosterone per 100mg of total weight. Testosterone Suspension considerably raises the storing of glycogen in the muscle cells and because it is dissolved in water it becomes effective immediately.
Also making it different from other esterfied hormones is that it only keeps sustained and elevated testosterone levels for 2-3 days due to its micro-crystal design. This forces the user to inject Testosterone Suspension on a daily basis, with better results coming from twice to even three times a day use due to its short active-life with the effective dose ranging from 350-1000mg per week (50-140mg/day). One should practice site rotation and should practice injecting in the same spot only once per week at most.
It should be noted Testosterone Suspension is usually a very painful shot, so it is often cut with something else, such as B-12, or other steroids, and yes, you can mix a water based steroid with an oil based steroid in the same syringe. It looks like a lava lamp, and you can use it as a level if you are building something, but no, theres no problems with injecting a mixture like this.