Shepherd's whistle
They are also produced commercially. Simple whistles may cost less than 1 USD in bulk; expensive ones may be quite ornate. They are commonly made of plastic, aluminum, stainless steel, silver, brass, titanium, Corian, jade, buffalo horn and other materials.
Whistle (2003 film)
Whistle is a 2003 Tamil slasher film which is a remake of the English slasher film "Urban Legend". Although the film was an average grosser, its music became successful. The film has Sherin and debutant Vikramaditya in the lead role. With Vivek, Gayathri Raguram, Livingston, and Divyadarshini in supporting roles.