Portal 2 Aperture Lanyard Key Chain This patented black and white Aperture Laboratories personal item tethering system has been developed to ensure ease of use and minimal chance of combustion while idle. In addition, when used in optimal testing conditions Portal 2 Aperture Lanyard Key Chain has been shown to have a non-life-threatening failure rate of less than 50%. Note: item tethering system not compatible with potatoes.