R4i Gold 3DS Card backup for ntrboot flasher. It works on card revision C. It may work on other revisions. Depending on the version of the flasher, you'll have to rename the backup file.
That looks like the router i just got from microcenter. Spectrum wanted to charge me $7 a month for a wifi router, so I said no thank you and just bought one, I paid like $65 tho