ZigBee motion sensor similar to iris

I love the size of the Lowes iris motion sensor compared to the zwave sensors it is much smaller.

I have found on line there is a company called alert me who seems to make them but have not been able to find anywhere that sells them. Has anybody been able to find a ZigBee small motion sensor for sale?

The SmartThings version is pretty small and it works well. I got one with a kit I bought. It is a ZigBee based device:

+1 I love the ST motion sensor

2.6x2.6" is still bigger than the Iris motion sensor. I also love the Iris ones due to their size.

I found this: