Keto is abbreviated for Ketotifen. It is an antihistamine. It inhibits the down regulation of the same beta 2 receptors clenbuterol stimulates. It basically makes clen more effective. I talk about it more in this article:
http://www.evolutionary.org/clenbuterol-steroids-side-effects
The real take home point of the article is that clenbuterol often does more harm then good. It is a harsh stimulant that does not differentiate between muscle or fat loss.
There are much better options.
Cardarine GW stacked with n2slin is going to be your best option.
http://needtobuildmuscle.com/store/F...2Slin-p50.html
http://www.evolutionary.org/cardarine/
Cardarine is drug that binds to the PPAR receptor and is non-hormonal. Cardarine increases the expression of genes involved in the expenditure of energy, stimulates glucose uptake in skeletal muscle tissue and burns fat by stimulating fatty acid oxidation.
N2slin is a non-stimulant fat burner and powerful nutrient partitioner. It increases insulin sensitivity of muscle cells and helps partition the food you eat into muscle cells and away from fat cells.
Both are stimulant free and non-hormonal.