@TanookiWhich one did you get? The homebrew stuff is now easily my favourite part of gaming.
I received these in the mail yesterday from a friend who is selling his collection. This guy was a large local collector, so I've been buying what I can from him since the summer, sadly some things I'm missing he had sold before I had a chance to get them, haha.
These carts are old bootleg cartridges, locally they're referred to as "NIG" carts, but upon closer inspection it seems they might actually read NTG, perhaps meaning Nintendo TV (Game) or New TV (Game).
Games include Wrecking Crew, 20 in 1, Super Mario Bros, Baltron, Route 16, Flappy, City Connection, Battle City, Hogan's Alley, Pac-Land, StarForce, Goonies, Valkyrie, and StarForce.
Some have ID codes on the back, I'd love to know or document all of these but it'll be impossible, many have nothing stamped.