What are Super Strength Green Tea Capsules? BULK POWDERS™ Super Strength Green Tea Capsules are an award-winning, ultra potent form of Green Tea Extract, containing 95% Polyphenols, 70% Catechins, 45% EGCG & 7% Caffeine. In comparison, most Green Tea supplements contain around half these amounts, at best. The reasons for supplementing with a good quality Green Tea supplement are vast. It's health & performance benefits, plus its positive effects on body composition make it a must