Not sure. You have to buy/put a deposit for the device. Then you just connect it with a CC, bank account, etc for refills when you use up what $ you deposit in the device. When you've gone thru what you initially deposit, it will auto withdraw from whatever acct you set it up with. You can check your balance/usage online to get an idea of when the refill will happen, how often it's used, when/where it's used, manage your acct & settings, etc. Last I heard, with i-pass, you pay 1/2 what it would be if you paid at $ booths.
To buy an I-Pass costs $30.
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