Demand has been high on a good whistle in aluminum. It is lightweight and very comfortable to hold in his mouth and have an incredibly good sound over long distances. The design is based on a variant of the shepherd's whistle that has been in Britain for many years. Without "ears" for those who like it better. Production has been down for many years, but now you can buy it again. Available in: Aluminium, Blue, Black and Red. 

For an additional charge you can get custom-size hole diameter.

The standard hole is 2.3 mm