There are also some security risks in RFID. To prevent theft of information in RFID, in November 2010, 2.5 million radio frequency shielding sleeves were delivered to the DoD, and another roughly 1.7 million more were to be delivered the following January 2011.[13] RAPIDS ID offices worldwide are required to issue a sleeve with every CAC.[13] When a CAC is placed in a holder along with other RFID cards, it can also cause problems, such as attempting to open a door with an access card when it is in the same holder as a CAC.