Mad of ABS , , firm and stable for us to use. Handles extreme heat and maintain its structural integrity for long life out of your speakers. Protects the voice coil and provide the optimal sound each and every time. Piezoelectric : coal, speakers, KTV, stage, horn , piezo tweeter horn , piezo design, sound harsh, very suitable for coal, a bird catcher, also suitable for small KTV stage sound. Piezoelectric Tweeter only, other accessories in the picture is not included.