Here you can buy the key EARTH DEFENSE FORCE 4.1 - Ranger Weapons: Sting Shot DLC (addition to EARTH DEFENSE FORCE 4.1 The Shadow of New Despair) at a bargain price. After purchase, you will immediately receive a key, activating which you will add DLC to the game EARTH DEFENSE FORCE 4.1 The Shadow of New Despair to your steam account.

Without the original EARTH DEFENSE FORCE 4.1 The Shadow of New Despair game on your account, you will not be able to activate Sting Shot.

https://store.steampowered.com/app/473441/Sting_Shot/

You can activate the key in any region.

Key activation instructions:
1. After purchase, you receive a unique key that you need to copy and enter into the Steam client.
2. Opens steam. We are looking for the button "Add game" in the lower left corner, then click on "Activate in steam"
3. In the appeared window, insert the format key - HHHHH-HHHHH-HHHHH
4. After activation, the game will appear in your library.