Taco Bell promised it would play a leading role in fast-food’s accelerating value wars. The chain just took its first swing of 2018. The company announced it will begin selling Nacho Fries for a limited time starting January 25. The price: $1.

Taco Bell said in early December it would unveil 20 new $1 menu items in test markets and nationwide in 2018. There are already 20 items on its extensive dollar menu, and the $1 Stacker joined the lineup December 21.

The Fries are part of Taco Bell’s offerings internationally, and was tested in West Virginia and California last spring. The seasoned fries are served with a side of nacho cheese. Guests can make the order “Supreme,” for $2.49, which adds pico de gallo, beef, and sour cream. Diners can also elect for the fries to come “Bell Grande,” which features the Supreme toppings but arrives as a larger portion.

Taco Bell will also offer the Nacho Fries in its popular $5 box, joining a Doritos Locos taco, Cheesy Gordita Crunch, and medium drink.

Taco Bell made its $1 push in 2014 when it announced 11 offerings as part of a value menu “that shows how $1 unlocks opulence.”

The Yum! Brands chain told CNBC that its $1 menu items produced more than $500 million in sales last year and its $5 boxes generated an additional $1 billion.

Taco Bell reported worldwide system sales growth of 6 percent in the third quarter versus the prior-year period. Yum! opened 70 Taco Bells in the quarter to bring its total count to 6,738. In the third quarter, the company debuted 15 new international units. Operating margin increased 3.5 percent points driven by refranchising and same-store sales growth partially offset by food and labor inflation.

Same-store sales growth is up 5 percent year-to-date so far for Taco Bell. That’s a healthy boost from the 1 percent gain it reported in 2016.

In December, Taco Bell also revealed its plan to pour resources into digital for 2018, including expanded delivery and self-serve kiosks.

Taco Bell’s move joins a growing pool of value-based offerings in quick service. McDonald’s entered the New Year with a $1 $2 $3 Dollar Menu to replace its McPick 2 Menu. The $1 $2 $3 Dollar Menu has three price points built around customization. Each tier allows guests to pick from breakfast, burger, chicken, and beverage options.

On Wednesday, Wendy’s joined in with an expanded 4 for $4 menu that now features eight entrées, including menu items served with premium chicken, oven-baked Applewood Smoked Bacon, and of course, fresh never frozen beef.