what is it?

问题描述:

what is it?
it is usually made of metal.it is round on one end.It can be very small,small enough to fit in your pocket,or large,but not as large as a car.it is used to make noise.it can be used to give a signal.Sometimes it's part of an orchestra.Sometimes it is electric and you push a button to make it ring.

cell phone /mobile phone?whistle?