MBTA buses are rolling into Black History Month bearing a new tribute to Rosa Parks.

In keeping with a law signed last month, the buses are now sporting red decals that say "Remembering Rosa Parks and the Montgomery Bus Boycott" and feature a photo of Parks.

Parks, in December 1955, refused to cede her seat on a Montgomery, Alabama bus to a white passenger, sparking a yearlong bus boycott in that city that ended after the U.S. Supreme Court ruled segregation on public transportation was unconstitutional.

Gov. Charlie Baker on Jan. 9 signed a law tasking the MBTA with acknowledging "the contributions of Rosa Parks to the civil rights movement using a light-emitting diode display or decal in the front left window of the bus, or in a similar manner approved by the authority."

"In doing so, we are honoring, in my estimation and the estimation of millions of people, an American patriot who obviously was an icon in the civil rights movement and still is," Sen. Walter Timilty, who sponsored the bill, said Tuesday. "I think it's important to recognize great people who have done great things for our country."

Timilty's original bill, which he filed after a constituent suggested the idea, called for Parks to be honored on the T's buses during Black History Month each February. Before passing the bill, lawmakers agreed to a Rep. Ted Speliotis amendment extending the recognition year-round.

Timilty, who visited the MBTA bus depot in Quincy Monday to see the stickers, said they will send "a very positive message."

"It constantly reminds people, all of us, how to live our lives and what is important in our society," the Milton Democrat said.