This company is selling adapters that will allow you to shoot different ammo than your weapon was designed for. Check out this glowing ad right from their webpage:
Now you can turn your 308 or 30-06 into a 7.62x39 and take advantage of inexpensive ammo!
One little problem there: Western .30's are .308, and Russian .30's are .311. Repeated use of Russian ammo in a .308 barrel will positively ruin the bore. Yeah, way to sell a product to the uneducated masses that will cause them to destroy their firearms.
And how do their little adapters work? They're supposed to be Loctited into the chamber and act as a sleeve around the casing. Do I even have to say why this is a bad idea, putting Loctite in your chamber? Or trusting this tiny insert to be able to handle the pressures of firing and not split and permanently damage your gun?
Add them to the Wall of Shame!