FREE FOR ACTIVE DUTY/PRIOR MIL (Limited Time on 10/25)

This is only for a limited time - so, once it's gone it's gone. Get it while you can.
I got mine for free! Go here (Or search COD Endowment USAA Tracer ID ME):

Step 1: Go to https://hosted-pages.id.me/activision-call-of-duty-usaa-military

Step 2: Click the Green "Verify with ID.me" and sign in. Once that finishes you should see your "Call of Duty Endowment Endeavour: Tracer Pack"

Step 3: Click the Copy button. (If you missed it, you can just go back to the previous page, verify your ID.me and get your code back)

Step 4: Click the "Continue to Activision" button.

Step 5: Log in to Activisions site. Once logged in, you can paste the code and make sure you have Steam selected as the platform (If you don't have steam selected, you can link it).

Step 6: Activision will give you your Steam Code (At the bottom below the Tracer Pack picture). Copy the steam code.

Step 7: Open Steam and at the bottom left click "Add a game" and then "Activate a product on Steam".

Step 8: Paste the code from Activisions site and redeem.