NDS:N-Card
The N-Card was created by a Chinese company, DSGBA, which specialises in manufacturing DS and GBA flashcards. These cards come in a number of different capacities, either 1GBit or up to 16GBit of storage, and often use either Samsung or Hynix NAND flash chips.
The card can be connected to a PC using the provided slot-2 adapter, so it can be used just like a USB flash drive, while also having the ability to flash a new UDisk if the card is booted to a recovery mode. A number of clones were made by different companies, varying in features and better game compatibility; the DS Fire Link, N-Card, and the DS Linker were the most common.
Kernels
All N-Card originals and clones use exactly the same hardware, so firmware from another card can be cross-flashed.
Ultra FlashPass EX: uDisk v1.45, xMenu v2.52
N-Card: uDisk v1.45, xMenu v2.55
DS Fire Link: uDisk v1.45, xMenu v2.55
DS Linker: uDisk v1.45, xMenu v2.55
Ultra N-Card: uDisk v1.23o
NeoFlash MK5: uDisk v1.45, xMenu v2.56
Utilities
nrioTool - A tool for dumping the hidden SRL ROM sections, it can also be used to recover bricked carts.
XuluMenu - Custom uDisk firmware replacement for N-Card (original/clones).
nrioSaveTester - SRAM tester to check if the internal battery had died.
Websites
Ultra FlashPass EX: www.dsgba.com
N-Card: www.dsgba.com / www.superdslink.com / www.ncardhk.com / www.ncard.com.tw
DS Fire Link: www.dsfirelink.com / www.dsfirelink.nl / www.dsfirelink.net
DS Linker: www.dslinker.com / www.dslinker.cn
Ultra N-Card: www.ultracard.cn
NeoFlash MK5: www.neoflash.com