Transdermal products are becoming available, but are inconvenient and furthermore have the disadvantage of delivering the product slowly and steadily over relatively long periods of time. This means that one cannot have high levels specifically during one’s workout, or just during the day but not at night: one is going to have the same levels all the time. This means that if enough is being used to be effective in helping build muscle, it will also be effective in shutting down natural LH production at night. Therefore, I don’t recommend the transdermals unless one is willing to sacrifice natural testosterone production. If someone wants gains at all costs, including shutdown of natural testosterone, then the transdermal products, particularly in combination with heavy oral or sublingual use, would make sense. A cycle of pharmaceutical AAS would make more sense though.