In context: Microsoft’s line of Windows Mixed Reality headsets—the wearable VR devices developed in partnership with companies including Dell, Asus, Lenovo, and HP—haven’t exactly been smash hits, which might explain why they are disappearing from online stores, including Microsoft’s.

The headsets were introduced back in 2017 and most have been available on Microsoft’s store since then. But RoadtoVR notes that for at least a week, the Windows Mixed Reality headset store page has shown just three headsets, and two of those are out of stock.

In the US, only the Samsung HMD Odyssey+ can be bought from Microsoft’s store, with products from Lenovo and Asus unavailable. In the UK, the only Mixed Reality headset listed is HP’s.

On Amazon, most of the Windows Mixed Reality devices are showing as being low on stock or unavailable, while Best Buy also contains products listed as either sold out or with clearance discounts.

RoadtoVR notes that this could be because of a common component stock shortage that has resulted in manufacturing delays, but there has been little interest surrounding the Windows Mixed Reality headsets since their launch two years ago, and some models might be getting discontinued.

Microsoft removing the headsets from its store might not be too much of a surprise. Earlier this year, a report by German site discovered the company would no longer be paying commission on the devices, which seem better suited to the enterprise market rather than consumers.