Use CardBus cards in your laptop ExpressCard slot. The CB2EC CardBus to ExpressCard Adapter converts a laptop ExpressCard port into a CardBus port, enabling you to use older CardBus cards with a newer (ExpressCard-capable) laptop computer. Ideal for use with Ethernet LAN, Broadband, Modem, and other CardBus expansion cards, this adapter eliminates the expense of replacing your existing CardBus cards for the sake of compatibility with a newer laptop computer. The CardBus to ExpressCard adapter supports common operating systems including Windows XP, Vista, and Mac OS X and up.