Carbolin 19 is a non-steroidal anabolic compound. It was designed to increase lean body mass and decrease fat mass, and as an added benefit, may increase testosterone production to a moderate degree in males.
RED KAT and Alpha Male were designed to increase your own body's testosterone production. Alpha Male is a combination of the active constituents from both RED KAT and TRIBEX. It's the better choice in my opinion.
Hope this helps.