 Apple also offered an application to enable 802.11 Draft-N functionality on these Macs for a fee of $1.99, or free with the purchase of an AirPort Extreme base station.Starting with Leopard, the Draft-N functionality was quietly enabled on all Macs that had Draft-N cards.This card was also a PCI Express mini design, but used three antenna connectors in the notebooks and iMacs, in order to use a 2 × 3 MIMO antenna configuration.