Why does BluTube have two straws instead of one?

While most straws/cartridges are sold as being a year-long treatment product, thousands of waterline tests have shown this is not the case. After about 7 months of use, the potency of antimicrobial in these products decreases to the point of being ineffective. That’s why every order of BluTube includes two straws, each to be used at maximum effectiveness for 6-months, to supply each operatory for an entire year.