The Chamber-View is a safety flag designed for semi-automatic and pump action shotguns with a side ejection port. It is made from solid silicone and is “Hunter Orange” in color. Because of its wedge shape (with teeth to grip the inside of the action), it will fit in shotguns from .410 gauge to 12 gauge in size. I don’t know for certain, but it may also fit pump action centerfire rifles.
Being solid silicone it is heavier than it looks and feels nice in the hand. The silicone is relatively soft so you can jam it in without worrying about damaging either the shotgun or the Chamber-View.
Its name is a misnomer. You cannot see the chamber. When the Chamber-View is inserted the bolt cannot close, nor can a round be inserted into the chamber. For most tube fed shotguns, you will be able to load or inspect the magazine. This may be an advantage or a disadvantage , or neither, depending on your point of view.
An added (minor) advantage of having the Chamber-View inserted into the action is that it prevents dirt getting into action. Personally when in the field I carry my shotgun with the chamber empty and the bolt closed, so this is not a problem I experience.
I enjoy teaching children to shoot clays, so it is great having a device like this to ensure they cannot fire a gun when they are not supposed to (it takes children a while to understand the basic safety rules and not violate them a couple of times per minute). At $9.99, it is a very useful tool that will not break the bank.