VRU

The Nintendo 64 VRU or Voice Recognition Unit (VRS or Voice Recognition System in Japan) was an accessory that plugged into the fourth controller slot on the Nintendo 64. On the other end was a microphone with yellow foam on it. It could connect to the back of the Player 1 Controller. In Japan it also came with a headset attachment. It was necessary to play Hey You, Pikachu! and as such was bundled with it. The VRU never caught on and the only other game to support it was Densha de Go! 64, a Japanese only train simulation game where it was an optional method of communicating with the passengers.

It could be considered the predecessor of the Nintendo GameCube Microphone as well as Wii Speak.