"These boxes are going to forward deployed troops that can't easily go shopping, you can't just maybe go buy a toothbrush," Julie DeMaria, Founder of Operation: Care and Comfort said.
Operation: Care and Comfort is a volunteer-run nonprofit based out of San Jose.
DeMaria says they've been putting similar care packages together for service members for more than two decades.
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On Tuesday, they partnered with the Greater NorCal Postal Customer Councils and USPS to fill, pack and ship more than 800 care packages to deployed troops.
"Of course during the holidays, we want to send a little holiday cheer, so there's stockings and ornaments and hand-written letters and all kinds of great stuff to let them know that we're thinking about them," she said.
San Francisco Postmaster Sunil Chanan says with close to 70,000 employed across the USPS nationwide, he says, this was the least they could do.
"You and me are talking here because of them," Chanan said. "We can express our emotions, everything, openly without being afraid because of the sacrifice they did for us. As a matter of fact, they are still out there protecting us."
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And the United States Postal Service is also using this event to let folks know about important shipping deadlines around the holidays.
"It can take weeks in some cases to get them directly to these military units in some undisclosed locations, so we want people to ship them early and also just the volume of mail at this time of year is crazy!" DeMaria said.
USPS says if you want it to arrive before December 25, priority cards and packages to military addresses overseas should be sent no later than December 9 and December 16 for express mail.