Abstract: The present invention relates to a rechargeable emergency card-type power bank for mobile devices, comprising: a battery cell having capacity adapted to recharge a mobile device to enable an emergency operation to be performed; a discharge cable suitable to provide charge from the battery cell to an electrical device; and a recharge port, configured to receive a power cable connector through which the battery cell may be recharged; wherein the power bank comprising reduced size and weight suitable to fit a credit card pocket of a wallet. A further aspect of the present invention relates to a mountable air purifier device that works in tandem with the power bank. The air purifier provides protection to the user from airborne diseases and other particular matter that may be hazardous to the user.