Dog tag

Dogtag a collectable item in Metal Gear Solid 2. To collect them hold up a guard and while they have their hands up get in front of them and look at them in first person view if there is a twinkle on their chest then they have a dogtag. You can make them give up the dogtag by aiming at their head or groin. They will then shake dogtags and other items free for you to pick up.

Some of the Guards will refuse to give you anything saying something like "are you going to shoot me?" shoot them in an arm or a leg. If you don't they will eventually duck and attack you.

Some of the bosses also have dogtags you can get them by picking them up and dragging them while they are knocked out.

You can view dogtags by going into the special menu and selecting Dogtag viewer