OPINION

Nathaniel Coleman, a prisoner at the Federal Correctional Institution (“FCI”) Allenwood, appeals pro se from an order denying his motion for sentence reduction. Because no substantial question is presented by this appeal, we will summarily affirm the order of the District Court. See 3d Cir. LAR 27.4; I.O.P 10.6.

As the parties are familiar with the background of this ease, we will only summarize those facts relevant to the disposition of this appeal. In December 1985, Coleman was convicted of conspiracy to murder a federal witness, in violation of 18 U.S.C. § 241, and obstructing justice, in violation of 18 U.S.C. § 1503. He was sentenced on August 5, 1987 to life imprisonment, and his judgment of sentence was affirmed on December 1,1988.

On March 29, 2003, Coleman performed the Heimlich maneuver on a young girl visiting FCI Allenwood who was choking on a piece of food. As a result of this heroic act and because he has had no disciplinary infractions since his commitment to the Bureau of Prisons, on February 23, 2009, the FCI Unit Manager recommended to the Warden that Coleman be awarded a 30-day lump sum award of extra good time. On September 22, 2009, Coleman filed a motion requesting that the District Court reduce his sentence because he saved the young girl’s life. By order entered May 27, 2010, the District Court commended Coleman’s actions, but denied his motion because the relevant Federal Rule of Criminal Procedure authorizes a *124 district court to reduce a sentence only within 120 days after the sentence has been imposed or affirmed on appeal. Coleman appeals. 1

The District Court granted Coleman’s motion for extension of time to appeal; therefore, his appeal was timely. See Fed. R.App. P. 4(b). We have jurisdiction pursuant to 28 U.S.C. § 1291, and exercise plenary review over the District Court’s legal conclusions. United States v. Fried-land, 83 F.3d 1531, 1538 n. 4 (3d Cir. 1996).

The District Court properly concluded that it could not reduce Coleman’s sentence under former Rule 35(b) of the Federal Rules of Criminal Procedure. 2 Former Rule 35(b) authorized “district courts to reduce a sentence within 120 days after it is imposed or after it has been affirmed on appeal.” 3 United States v. Addonizio, 442 U.S. 178, 189, 99 S.Ct. 2235, 60 L.Ed.2d 805 (1979). Coleman’s motion was filed more than twenty years after his sentence was affirmed on appeal.

Accordingly, we will affirm the District Court’s order denying Coleman’s motion for reduction of sentence.