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For the third time this season, the Cowboys will be making a change to their helmet, and this time around, they'll be featuring a look that they've only worn a total of two times over the past 46 years.

When Dallas kicks off against Indianapolis on Sunday night, the Cowboys will be wearing a red stripe on their helmet. The Cowboys' helmet usually features a white stripe down the middle that's flanked by two blue stripes, but for the game against the Colts, one of those blue stripes will be red. 

The Cowboys will be wearing the stripe to go full "red, white and blue" since Sunday will be their Salute to Service game. Not only did they add the extra stripe, but the team will also be honoring 17 Medal of Honor recipients at the game. 

The game against the Colts will mark just the second time since 1976 that the Cowboys have worn the red stripe on their helmet. The Cowboys actually wore the red stripe during the entire 1976 season -- to honor America's bicentennial -- but after that, they didn't bring the stripe back out of the closet until last year when they wore them in a November game against the Broncos

To add to the Salute to Service night, the entire offensive line will be wearing cleats to honor the National Medal of Honor Museum Foundation. Cowboys guard Zack Martin is one of nearly 50 people, including coaches, who will be wearing the cleats. 

"We thought it would be a really cool thing to honor those recipients with the entire offensive line," Martin said Thursday, via the Dallas Morning News. "It really is humbling. I got a chance to meet 'Flo' (retired U.S. Army Capt. Florent Groberg), a Medal of Honor recipient, a couple weeks ago. I just think it's so cool. I don't think a lot of people understand the sacrifice that these guys have gone through.

As for the red stripe, it marks the Cowboys' third different helmet look this year. Besides, their normal helmet, the Cowboys also wore a white helmet on Thanksgiving. 

In Week 17, the Cowboys will be unveiling another look when they wear their arctic white helmet for the first time ever. 

As for the red stripe, you can see it Sunday night when the Cowboys and Colts kick off at 8:20 p.m. ET on NBC.