L-citrulline is where its at. I would suggest checking out purebulk.com. myself and many other brothers have had good luck with them. I order a kilo at a time, and take 4-6 grams a day, just mixed with water and drink it down. Combined with the [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]penomet[/words] and kegels, my erections are ridiculous, I'm pushing 40 and its like I'm 17 again.