The XMG walker is a backpack PC by Schenker Technologies GmbH. Current high-end virtual reality head mounted displays (HMDs) are tethered HMDs, meaning they are connected to a high-end computer with very good graphics processing capabilities for rendering the virtual environment. This tethered HMDs continue to present a challenge for a fully immersive virtual experience, because the user is bound to move only within the limits of the length of the cables. The user also often gets entangled with cables in the real world as they move and rotate in the virtual environment. Possible solutions to overcome this have been the use of wireless transmitters (for transmitting the signals wirelessly from the workstation to the HMD) and backpack PCs (lightweight high-end graphic processing computers, that the user straps to the back with short cables directly connected from the HMD to the PC).