GO2 Endurance Workout Device for Improved Breathing and Increased Oxygen Flow While Running, Biking/Cycling, Exercising, Hiking and High Altitudes Made in The USA

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SCIENTIFICALLY PROVEN: We had independent PhD Scientists test GO². The results: GO² improved VO2 Max by 4% and Endurance by 6%. Oxygen is what fuels your mind and body.
BEST QUALITY: With a large breathing hole, GO² provides a seamless inhale while harnessing proven scientific principals of PEEP (Positive End Expiratory Pressure) to increase oxygen on the exhale. Hospitals have used PEEP to help people breathe better for 40 years, so you know it works! The result: improved stamina, peak performance, and clearer thinking.
EASY TO USE: Easy to use and comfortable to wear, GO² is suitable for athletes with or without braces on their teeth; also one size fits most – just bite down and you’re set.
100% GUARANTEE: We stand by our product. If you are not 100% satisfied, contact us directly (even if after the Amazon return window) and we will provide you with your choice of a hassle and cost free replacement or refund. We stand by our product!!
Designed by Doctors in the USA and 100% Legal by WADA rules