Viper-X Blackstone LabsViper X by Blackstone Labs Caffeine Anhydrous (250mg) is well known for its energy boosting properties, but its also an extremely effective fat burning agent. Caffeine liberates stored fatty acids to be burned off for energy, laying the foundation for the other fat burning ingredients included in ViperX. Caffeine also helps fight the lethargy and brain fog that sets is while dieting, and its also a pretty effective appetite suppressant too, helping