Argued March 21, 2013
On Appeal from the United States District Court for the Eastern District of Pennsylvania District Court No. 2-11-cr-00227-003 District Judge: The Honorable R. Barclay Surrick
Andrew J. Schell [ARGUED] Office of United States Attorney
Counsel for Appellee Christopher G. Furlong [ARGUED]
Counsel for Appellant–Davis Mark E. Cedrone [ARGUED]
Counsel for Appellant–Blackshear 
Before: McKEE, Chief Judge, SMITH, and GREENAWAY, JR., Circuit Judges
SMITH, Circuit Judge.
Police arrested Terrell Davis after finding him in a Jeep with nearly a kilo of cocaine in the backseat. The arrest led to a conviction for possession with intent to distribute. As evidence that Davis recognized the cocaine in the Jeep, the government proved at trial that he had two prior convictions for possessing cocaine. Yet the government never proved that the cocaine from his past was similar in appearance, quantity, or form. We acknowledge that some of our cases admitting prior criminal acts under Federal Rule of Evidence 404(b) have been expansive. But our expansiveness is finite, and this case crosses the line. We will vacate Davis's conviction and remand.
The events at issue took place on a wintry after- noon over two years ago. Two Philadelphia police officers were patrolling near 5100 Market Street—roughly four miles west of Independence Hall and the Liberty Bell. This is a dangerous part of the city where drug deals and robberies are commonplace. Officer Clifford Gilliam parked his patrol car, and Officer Shawn Witherspoon joined him on foot. On the opposite side of the street, the officers spotted a black Jeep Grand Cherokee, later determined to be from Enterprise Rent-A-Car. Inside were two men, Terrell Davis and Jamar Blackshear. The Jeep's engine was running but nothing seemed amiss.
After a period of time, Davis and Blackshear began to act suspiciously. They reached toward each other with "body motions [that] were consistent with the exchanging of narcotics in a narcotics transaction." B.A. 8.The officers exited their patrol car and approached the Jeep. Upon noticing the officers, Davis and Blackshear had "expressions of shock on their faces, " B.A. 8, and they tossed something into the backseat. They exited the Jeep and quickly walked away—so quickly, in fact, that Blackshear did not bother closing his door. Officer Gilliam stopped Blackshear and patted him down to search for weapons. He instead found a wad of cash in his pocket. In the meantime, Officer Witherspoon stopped Davis and patted him down. He found a similar amount of cash.
Everything indicated to the officers that this was a drug deal: the suspicious movements, the hurried departures, the wads of cash, and the neighborhood itself. Knowing that guns often accompany drug deals, the officers decided to search the Jeep for weapons—and to see if there were any other occupants. Officer Witherspoon tried to look through the tinted rear window, but it was too dark. So he opened the already-ajar driver's door and saw a handgun wedged between the driver's seat and the middle console. At that point, the officers arrested Davis and Blackshear and placed them in the patrol car.
The handgun was not the only item in the Jeep. Officer Witherspoon returned and spotted an opaque shopping bag in the backseat. It was open and contained a white substance. The officers requested a drug-detection dog, which alerted to the presence of drugs. The officers obtained a warrant and recovered ten cell phones, a pair of binoculars, and two shopping bags with roughly 740 grams of cocaine distributed among nine smaller Ziploc bags. The cocaine itself was compressed into the shape of a brick and had a street value over $75, 000.
Davis and Blackshear were charged with pos- sessing a controlled substance with intent to distribute under 21 U.S.C. § 841(a)(1) and with possessing a firearm in furtherance of a drug-trafficking crime under 18 U.S.C. § 924(c). They were also charged with aiding and abetting under 18 U.S.C. § 2.
Davis and Blackshear filed a motion to suppress all evidence from the Jeep. They argued that because the Jeep's front driver's side window was tinted, the officers could not have seen the alleged reaching, gawking, and tossing—and so they could not have had any cause for suspicion in the first place. The District Court inspected the Jeep and discovered that the window was in fact tinted. The Court nonetheless denied the suppression motion. It credited the testimony of the officers who said that the window had been tint-free on the day of the arrests eight months earlier. It also credited the testimony of an Enterprise employee who said that neither Enterprise nor the manufacturer had tinted the windows and that since the arrests over fifty people had rented the Jeep.
The defendants then pursued separate paths. Blackshear pled guilty but reserved the right to appeal the denial of his suppression motion. He received two consecutive sixty-month sentences plus four years of supervised release. Davis opted for a jury trial. As the trial approached, the government asked permission to introduce Davis's two prior convictions for possessing cocaine. The District Court consented, stating that the convictions were admissible under Federal Rule of Evidence 404(b) to show that Davis recognized the drugs in the Jeep. At trial, the jury heard testimony from a range of witnesses, including Officers Gilliam and Witherspoon; Keith Fes-tus, the owner of a nearby cell-phone store; and a narcotics expert. The jury ultimately found Davis guilty of the drug crime but not guilty of the gun crime. He received a seventy-eight-month sentence plus four years of supervised release.
Davis raises four issues on appeal: the denial of his suppression motion, the admission of his prior convictions, and ...