Idea of Commercial Icon
This is a megaphone. There is a handle on the megaphone on the left hand side and a large cone or funnel shape on the right hand side. There is a small half circle protruding from the flat part of the cone of the megaphone.
This page shows the different variations of the Commercial from an Icons8 icon pack. Feel free to resize and recolor the icon, and then download the icon in PNG format for free.