Other products that are knock offs of this do not perform like this item

Don't buy the knock offs

A lot of reviewers seem to say that they received knock offs

Don't waste money on knock offs

Don't mess with knock offs to try and save a few dollars

Just remember that different vendors sell this product, which can be viewed here: http://www.amazon.com/gp/offer-listing/B000HZFCT2/ref=dp_olp_new?ie=UTF8&condition=newAs a result of this, one vendor might be selling the actual Microsoft receiver, but others might be selling knock offs.

The one we ordered from a third party was a knock-off and doesn't work; knock-offs should not be sold under descriptions of genuine products.

Some of the reviews on here complain of knock offs

This is a genuine Microsoft product, which was a relief after seeing many cheap knock-offs

Apparently there are a ton of knock offs being sold, but this appears to be the official receiver by Microsoft

But be careful thought their is a lot of rip off sellers selling imitation knock offs.