Study your cardiac rhythms while keeping hydrated! Nicer looking than an EKG pocket guide, this Heartbeat Flask is both functional and aesthetic. Fill it with ice cold water and take it to the gym for your cardio workout, or top it off with herbal tea for a long night shift in the cardiac ward.  With a textured design for a unique tactile experience, this flask will keep your drink hot or cold until you're ready to enjoy it.