Made from strong heat treated, hardened steel. Comes in black version or silver colored versions. Silver colored versions are nickel plated, and are made from heat treated, hardened steel. Thus, the silver version is of the 3.8mm & 4.5mm security bits are much stronger than the black version.
The bits measure 5 cm (about 2 inches) in length and will fit any standard 1/4" screwdriver handle.
The 3.8mm security bit opens games for Original Nintendo (NES), Super Nintendo (SNES), Nintendo 64 (N64), Virtual Boy, Original Game Boy, Game Boy Color, and Sega Game Gear.
The 4.5mm security bit allows you to open Sega Genesis, Sega Master System, and Sega 32X games.
Additionally, the 4.5mm security bit allows you to open Super Nintendo, Nintendo 64, Game Cube, Virtual Boy, Game Gear, TurboGrafx 16, and TurboDuo systems (video game consoles).
Opening those games and systems will allow you a greater ability to clean and restore functionality. Additionally, it'll allow you, when necessary, to access a game or system's battery in order to restore save game functionality.