Also, as the judge noted, there was no unfair surprise to the defendant because he had known for a year that he had to defend against the charges related to the controlled buys, and they were dismissed only a few days before trial. See Commonwealth v. Belmonte, 4 Mass. App. Ct. 506, 507 (1976). Finally, the judge properly instructed the jury on the limited use of the evidence both after the testimony was given and again in his final charge.

Commonwealth v. Connolly, 356 Mass. 617, 627, cert. denied, 400 U.S. 843 (1970). See Commonwealth v. Ladetto, 353 Mass. 746 (1967); Commonwealth v. West, 357 Mass. 245, 249 (1970); Commonwealth v. DiMarzo, 364 Mass. 669, 682 (1974) (Hennessey, J., concurring); Commonwealth v. Boyd, 367 Mass. 169, 174 (1975); Commonwealth v. Belmonte, 4 Mass. App. Ct. 506, 511 (1976). The judge gave limiting instructions before the records of conviction were read and again in his charge that were sufficient to avoid any prejudice. Commonwealth v. Leno, 374 Mass. at 718-719.