Tribulus terrestris is a testosterone enhancer. It increases testosterone levels in a different way, however, than similar products DHEA or andro. Instead of being a testosterone precursor, it leads to the production of the luteinizing hormone (LH). When LH levels are increased, the natural production of testosterone also increases. LH is a hormone that also deals with sex drive. Now one can understand why it has been used to increase fertility and help with impotence. Laboratory animal studies found that Tribulus terrestris increased sperm count as well as motility levels after taking it for 30 days.
Supplement Facts:

Serving Size: 1 Capsule
Servings Per Container: 90

Amount Per Serving:

Tribulus Terrestris: 500mg
(standardized for 40% steroidal saponins)

Other Ingredients:
Gelatin, cellulose, silicon dioxide.

Directions: Take 1-2 capsules daily with meals.