KRAUSE, Circuit Judge.

In this consolidated appeal, Appellants John Gunther; his brother, Taleaf Gunther;

* This disposition is not an opinion of the full Court and, under I.O.P. 5.7, is not binding precedent. and William Roland challenge their convictions and sentences for various crimes related to their drug-trafficking operation in Camden, New Jersey. Because we see no error in the District Court’s rulings, we will affirm. I. DISCUSSION 1 Appellants raise a host of issues on appeal. Between the brothers, John Gunther maintains that his conviction was supported by insufficient evidence; both John and Taleaf Gunther argue that the District Court erred in its instruction to the jurors about how they should determine the relevant quantity of drugs; and Taleaf alone says the District Court wrongly denied his motion to suppress several intercepted phone calls. For his part, Roland argues that the District Court erred by allowing the Government to present cumulative testimony, refusing to issue a curative instruction, and denying his motion for a new trial. And all three defendants challenge their sentences as unreasonable on various grounds. We address these arguments in turn. 2 A. Sufficiency of the Evidence 3

John Gunther raises three challenges to the sufficiency of the evidence supporting his convictions under 21 U.S.C. §§ 841(b)(1)(A), 841(b)(1)(B), and 846. None is persuasive.

First, John faults the Government for proving up the net weight of the substances attributed to him containing cocaine base by extrapolating from randomly tested samples instead of testing each item. J. Gunther Br. 12–13, 40–42. But there is no requirement of individual testing. To the contrary, a drug quantity may be extrapolated from a test sample so long as “there is an adequate basis in fact for the extrapolation” and “the quantity was determined in a manner consistent with accepted standards of reliability.” United

States v. McCutchen, 992 F.2d 22, 25–26 (3d Cir. 1993). Both criteria are met here because, as the forensic chemist testified at trial, the tests conducted on the drugs followed a standard and accepted methodology for drug testing and extrapolation. J.A. 1365–68.

John’s second argument is that the Government failed to prove that he knowingly joined or had specific intent to further the drug conspiracy. J. Gunther Br 11, 14, 25. Yet voluminous evidence in the trial record shows otherwise. Testimony established that John

managed the drug operation and controlled the drug set’s crack. J.A. 1211, 1217–18, 1270, 1300–01, 1335. Seized mail and testimony established that although the Blackwood, New Jersey apartment—where a search revealed substantial evidence of drug trafficking—was

not in his name, John resided there with his girlfriend, id. 464–65, 486–87, 499, 528–29, 582, 1657–58, 1682, 1764. John’s intercepted phone calls, too, showed that he was a sales contact and central part of the conspiracy, id. 2274, 2278–79, 2299, and that he referred to the Blackwood apartment as “my house” and indicated to others that he lived there. J.A.

2352–53. In view of this evidence, it cannot be said that no “rational trier of fact could have found the essential elements of [John Gunther’s convictions] beyond a reasonable doubt.” Jabateh, 974 F.3d at 300.

The trial record also defeats John’s third claim, which is that the Government did not prove he possessed with intent to distribute furanyl fentanyl and heroin on February

22, 2017. J. Gunther Br. 43; J.A. 1217–18. The video surveillance footage from that day showed both John and Taleaf on the block of 1700 Filmore shortly before Taleaf left to sell drugs to a confidential informant. J.A. 891. Pen register intercepts showed that immediately after Taleaf received the informant’s order, Taleaf called a number associated

with John Gunther. J.A. 907. And surveillance footage established that, after the sale, Taleaf returned to 1700 Filmore and interacted with John. J.A. 902–03. The jury was

properly instructed about accomplice liability on this count, J.A. 1925–26, and on the evidence presented, a reasonable jury could find John Gunther guilty of aiding and abetting the distribution of furanyl fentanyl and heroin.

B. Purity Instruction 4 In their appeals, John and Taleaf Gunther both argue that the District Court erred by instructing the jury that “when determining whether the Government has proven beyond a

reasonable doubt the specific weight of the controlled substance, you are to consider the entire weight of the mixture and substance including any inactive ingredients, cutting agents, or diluents.” J. Gunther Br. 46-47 (quoting J.A. 1884); see also T. Gunther Br.

19. The brothers maintain that this “purity charge diluted the government’s burden of proof beyond a reasonable doubt” and thus reversal is required. J. Gunther Br. 46.

We will affirm a jury charge if it “fairly and adequately submit[s] the issue[] in the case to the jury.” United States v. Petersen, 622 F.3d 196, 203 (3d Cir. 2010) (quoting

United States v. Hart, 273 F.3d 363, 373 (3d Cir. 2001)). Here, there is no question that

the District Court’s instruction fairly and adequately stated the law. The relevant statute, 21 U.S.C. § 841(b)(1)(A)(iii), criminalizes certain acts involving “280 grams or more of a

mixture or substance described in clause (ii) which contains cocaine base.” Clause (ii), in relevant part, refers to a “mixture or substance containing a detectable amount” of cocaine.

Id. § 841(b)(1)(A)(ii)(II). Clearly, the statute is concerned with the total weight of the substance, not just the weight of the pure drug it contains. Chapman v. United States, 500

U.S. 453, 460 (1991). The District Court’s instruction accurately described this statutory scheme.

C. Motion to Suppress 5

Taleaf Gunther argues that the District Court should have granted his motion to suppress several intercepted phone calls. T. Gunther Br. 9. He contends that he was

impelled to make the calls by an unconstitutional stop-and-frisk, and that, therefore, the recordings should have been excluded as “fruit of the poisonous tree.” Id. at 15. We disagree. Law enforcement officers lacking a warrant may “conduct a brief, investigatory stop when the officer has a reasonable, articulable suspicion that criminal activity is afoot.”

United States v. Johnson, 592 F.3d 442, 447 (3d Cir. 2010) (quoting Illinois v. Wardlow, 528 U.S. 119, 123 (2000)). The Government searched 1700 Filmore based on months of surveillance, including evidence from the morning of the search showing that drug sales were taking place. J.A. 1103–07. Considering this ample evidence alongside testimony

that the Judge deemed “credible” and “corroborated,” the District Court did not err in finding that law enforcement had an articulable and reasonable suspicion of criminal

activity on Filmore Street, and that twenty to thirty minutes was a reasonable duration for a stop under the circumstances. J.A. 1136, 1140. See United States v. Sharpe, 470 U.S.

675, 685 (1985) (“[O]ur cases impose no rigid time limitation on Terry stops); see also

Baker v. Monroe Twp., 50 F.3d 1186, 1192 (3d Cir. 1995) (fifteen-minute detention during a drug raid was reasonable).

Even if Taleaf’s detention was unconstitutional, it did not taint the phone calls. J.A.

1141. See United States v. Pelullo, 173 F.3d 131, 136 (3d Cir. 1999). In the one call in which he discusses being stopped, Taleaf voices distress over co-conspirators’ arrests, not his own detention—which, again, was lawful. J.A. 2321. In considering the facts

surrounding Taleaf’s phone calls, then, the District Court did not commit plain error, and in exercising plenary review over its decision to deny Taleaf’s suppression request, we affirm.

D. Roland’s Abuse of Discretion Claims 6

Roland asserts that the District Court abused its discretion by (1) allowing the Government to present testimony that was “unnecessarily cumulative” under Federal Rule

of Evidence 403, Roland Br. 23; (2) by declining to issue a curative instruction during the Government’s rebuttal summation, Roland Br. 15; and (3) by denying his motion for a new trial, Roland Br. 26. In our view, none of these rulings constitutes an abuse of discretion.

First, Roland challenges the testimony of Joseph Eden, a K-9 officer, as cumulative

evidence that merely repeated the testimony of FBI Special Agent Dustin Poulin. Roland Br. 25. “Evidence is ‘cumulative’ when it adds very little to the probative force of the other evidence in the case, so that . . . its contribution to the determination of truth would be outweighed by its contribution to the length of trial.” United States v. Cross, 308 F.3d

308, 326 (3d Cir. 2002) (quoting United States v. Williams, 81 F.3d 1434, 1443 (7th Cir.

1996)). That is not the case here, where Agent Poulin’s credibility had been impeached on cross-examination. J.A. 593. Officer Eden’s testimony was introduced partly to bolster

Agent Poulin’s credibility, and it consumed just over twenty minutes of a multi-day trial.

J.A. 589–607. The District Court thus acted well within its especially broad discretion to admit the testimony under Rule 403. United States v. Sussman, 709 F.3d 155, 173 (3d Cir.

2013).

Second, Roland maintains that the District Court should have given a curative

instruction because the Government’s summation rebuttal “wrongly impressed upon the jury that counsel had intentionally attempted to deceive them as to the law governing the case.” Roland Br. 15. In response to defense counsel’s argument that Roland was not part of the drug conspiracy because he didn’t share “an intention to further [its] goals,” J.A.

1978, the prosecutor said: “[I]f Judge Bumb instructs you that as a matter of law, every member of a co-conspiracy has to be best friends with everybody else, well, then, I guess you go back there and find them all not guilty. But she’s not going to instruct you on that because that’s not the law. [Roland’s counsel] knows that.” J.A. 2032.

Roland’s lawyer did not object. Later, after the prosecutor said that John’s attorney

“ignore[d] pretty much all of the facts in this case in a pretty amazing quantity,” the Judge

summoned counsel to a sidebar, where she admonished the Government for “attacking the integrity of the [defense] attorneys” and urged the prosecutor to rephrase her arguments “in terms of the defendant, not the attorneys.” J.A. 2033–34. Roland’s attorney then requested a curative instruction, which the District Court declined to give. J.A. 2034.

The Court did not abuse its discretion in doing so. The Supreme Court has said that

“a criminal conviction is not to be lightly overturned on the basis of a prosecutor’s comments standing alone,” United States v. Young, 470 U.S. ^[1], 11 (1985), but only when

those comments can be said to have “so infected the trial with unfairness as to make the resulting conviction a denial of due process,” Darden v. Wainwright, 477 U.S. 168, 180–

81 (1986) (quoting Donnelly v. DeChristoforo, 416 U.S. 637, 643 (1974)). Here, the Government’s comment about Roland’s counsel was isolated, and however ill-phrased, it

was not gratuitous, as it was responding to the counsel’s claim that Roland was not part of a conspiracy. In a supplemental opinion, the District Court affirmed that it was legitimate for the government to argue that a lack of friendship among co-conspirators does not necessarily mean there was no conspiracy and that its warning against ad hominem attacks was “well received” and heeded by the Government, which had presented “overwhelming” evidence against Roland. Suppl. Op. to Prior Order at 8, United States v. Roland, No. 1:17-

cr-00488-RMB-2 (D.N.J. July 13, 2022), ECF. No. 329. With these considerations in mind, we hold that the District Court did not abuse its discretion.

Roland’s third argument is that the District Court abused its discretion in denying

his motion for a new trial because the guilty verdict was contrary to the weight of the evidence. Roland Br. 26. A district court may grant such a motion “only if it believes that there is a serious danger that a miscarriage of justice has occurred—that is, that an innocent person has been convicted.” United States v. Silveus, 542 F.3d 993, 1004–05 (3d Cir. 2008) (quoting United States v. Johnson, 302 F.3d 139, 150 (3d Cir. 2002)). We have

held that new trial motions “are not favored” and should be “granted sparingly and only in exceptional cases.” United States v. Brennan, 326 F.3d 176, 189 (3d Cir. 2003).

This is not one of those cases. As noted above, the District Court found that

“overwhelming evidence”—including drug packaging and residue discovered at Roland’s

apartment, Roland’s drug sales to confidential sources, and his intercepted phone calls and text messages—supported Roland’s conviction. Suppl. Op. at 8. It properly exercised its discretion in reaching this conclusion.

E. Reasonableness of Sentences 7

Finally, Roland and the Gunthers challenge their sentences’ reasonableness. 8 “[I]f the district court’s sentence is procedurally sound, we will affirm it unless no reasonable

sentencing court would have imposed the same sentence on that particular defendant for the reasons the district court provided.” United States v. Tomko, 562 F.3d 558, 568 (3d

Cir. 2009) (en banc).

All three Defendants argue that the amounts of drugs attributed to them for sentencing purposes were insufficiently proven, J. Gunther Br. 49; T. Gunther Br. 29;

Roland Br. 29, but we disagree. We have recognized that, “in calculating the amounts involved in drug transactions, some degree of estimation must be permitted,” although

“mere speculation” is forbidden. United States v. Collado, 975 F.2d 985, 998 (3d Cir.

1992). The evidence that a district court relies on in making its calculation need not be admissible at trial, but it must “have sufficient indicia of reliability to support its probable accuracy.” United States v. Freeman, 763 F.3d 322, 337 (3d Cir. 2014) (quoting United

States v. Brothers, 75 F.3d 845, 848 (3d Cir. 1996)). We review a district court’s findings of fact regarding quantity of drugs for clear error. Id.

John and Roland (and, by incorporation, Taleaf) claim that the District Court looked only to the uncorroborated testimony of one cooperating witness in calculating the amount

of drugs involved in the transaction. J. Gunther Br. 50; Roland Br. 30; T. Gunther Br., 29. Not so. In addition to the testimony, the Court considered intercepted calls, law enforcement testimony, surveillance footage, the seized drugs, and lab reports. Suppl.

App. 232–36. The Court did not commit clear error in finding this evidence a sufficiently reliable basis for 1) estimating the total amount of drugs involved in the conspiracy and 2) concluding that as members of an established drug conspiracy, Appellants reasonably could have foreseen the amounts attributed to them. See United States v. Perez, 280 F.3d

318, 353 (3d Cir. 2002) (“[A] defendant is accountable for all quantities of contraband with

which he was directly involved and, in the case of a jointly undertaken criminal activity, all reasonably foreseeable quantities of contraband that were within the scope of the criminal activity that he jointly undertook.”) (quoting U.S.S.G. § 1B1.3, cmt. n.2).

John Gunther also contests the substantive reasonableness of his sentence, but he

cannot cross that exceedingly high threshold. J. Gunther Br. 54–56. In reviewing for substantive unreasonableness, we consider the totality of the circumstances, and “we will affirm . . . unless no reasonable sentencing court would have imposed the same sentence on that particular defendant for the reasons the district court provided.” Tomko, 562 F.3d

at 568. The District Court offered a thorough explanation of its decision, J.A. 2184–92, that demonstrated a “rational and meaningful consideration of the factors enumerated in 18

U.S.C. § 3553(a).” United States v. Seibert, 971 F.3d 396, 399–400 (3d Cir. 2020) (quoting

United States v. Grier, 475 F.3d 556, 571 (3d Cir. 2007) (en banc)). We therefore hold that the District Court did not abuse its discretion in imposing John’s sentence.

II. CONCLUSION

For the foregoing reasons, we will affirm Appellants’ convictions and sentences.