"Zhai Wo Zi" 
I recently enjoyed some time flying “Qi xiong” or sparrow hawks at magpies in the city streets and parks of China. We were hunting black and white magpies and blue pies and were often successful.
Riding on bicycles, the sparrow hawk is held in the palm of the hand until it is felt the approach is close enough, then the hawk is thrown like a dart at the magpie.
As the hawk fly's it carries a thin light line which streams out of the “Zhai Wo Zi” which is fastened to the falconers wrist. The line is not attached to the falconer, and follows the hawk through the trees. It is used as a means of recapturing the hawk.
This item is sold as a curiosity piece for a collector and I would not recommend anyone trying to use this item without the skill and knowledge of the Chinese falconers.
Since writing the above I have returned to China and enjoyed some hunting with a Jack Merlin. Riding bicycles 
through the village streets armed with the Jack in the palm of my hand ready to be thrown at any small flock of sparrows.
He was fast and very effective and I learnt a lot more in the use of the "Zhai Wo Zi" 
