contained in Government Exhibit 2, a National Firearms Registration and Transfer Record certificate offered to prove that Breeland’s firearm was not registered to him. The certificate contained the erroneous statement that the seri al number on the weapon had been obliterated (in fact, it had been manufactured without a serial number). Even if this statement improperly prejudiced the jury, as Breeland contends, its admission was harmless in light of the overwhelming proof of Breeland’s guilt. See Schneble v. Florida, 405 U.S. 427, 432, 92 S.Ct. 1056, 1060, 31 L.Ed.2d 340 (1972) (“[UJnless there is a reasonable possibility that the improperly admitted evidence contributed to the conviction, reversal is not required.”); United States v. Tomblin, 46 F.3d 1369, 1388 (5th Cir.1995) (<HOLDING>); United States v. Washington, 44 F.3d 1271,
holding that where there is competent evidence to support the courts findings the admission of incompetent evidence is not prejudicial holding that the district court committed plain error by admitting evidence obtained in violation of the fourth amendment where the error did affect a substantial right of the defendants and the admission of evidence which should have been excluded did have a prejudicial impact on the jury holding that erroneous admission of improper and prejudicial evidence did not require reversal because the jury would have returned a verdict of guilty against the defendant even without the prejudicial testimony holding that it is improper for a prosecutor to assume the existence of prejudicial facts not in evidence holding that the admission of expert testimony was prejudicial where the testimony was pervasive