https://www.vive.com/us/accessory/tracker3/

Price: $129.99

Description:

The first. The one. The only VR tracker. Create a seamless connection between real objects and the virtual experience. Capture full-body movement with pinpoint accuracy. Integrate external devices with ease. Take your VR to a new level with the VIVE Tracker (3.0). Now smaller, lighter, and longer-lasting than ever before. Only from VIVE – the pioneer of VR.