A device for automatically providing needles to a sealing apparatus for sealing a puncture in an anatomical structure, the sealing apparatus including a needle insertion lumen and a needle pusher channel having a needle pusher disposed therein. The device may include a housing coupled to the sealing apparatus and a cartridge disposed in the housing. The cartridge has a slot and a plurality of needles disposed, therein. The needle slot is aligned with the needle insertion lumen and the needle pushing channel.