As with many other online merchants and physical stores, Zuli may place an authorization hold on your credit or debit card account for the approximate amount of purchase you make. When you first submit a new order or update your billing information, we may place a temporary authorization hold on your credit card account, usually in the amount of $1 to verify your account information. If the authorization is denied, you may see a $0 temporary authorization. Most debit and credit card issuers will call this a "Pending" or "Temporary" charge on your online statement.
When your Smartplug ships, the full amount of the order will be charged, replacing the temporary authorization. "Authorization hold" (also called card authorization, preauthorization, or "preauth") is the practice within the banking industry of authorizing electronic transactions done with debit or credit card and holding this balance as unavailable either until the merchant clears the transaction (also called settlement), or the hold "falls off."
You might see authorization requests on your online statement. Authorization holds are removed by your financial institution shortly after your purchase clears or "settles". The time it takes to remove authorization requests varies by financial institution but in most cases will drop within a few business days.
Read more here: http://en.wikipedia.org/wiki/Authorization_hold