So it's an elevator box which has a number keypad in it with a 'enter' button. You type in a code of numbers and press enter and it makes a loud buzzing sound and then the door opens. Depending on the number it would have transported you to a random place. That place could be a elevator in a hotel or the middle of a field or back in time. The possibilities are endless. Each number will take you to the same place it always does. So typing in something like '173643' will always transport you to SCP 682's containment.
So please tell me your feedback and if it's mostly positive I will write it up in more detail with a few addendums.