A jury convicted the defendant of possession of cocaine with intent to distribute and an accompanying school zone offense.1 G. L. c. 94C, §§ 32A & 32J. On appeal, the *837defendant principally argues that the Commonwealth’s evidence at trial was insufficient as matter of law to prove beyond a reasonable doubt he intended to distribute cocaine.2 We agree.

Facts. Based upon the Commonwealth’s evidence, reviewed in the light most favorable to it, the jury would have been warranted to find the following. Commonwealth v. Latimore, 378 Mass. 671, 677-678 (1979). On New Year’s Day 2009, at 9:30 p.m., Trooper Robert Noonan of the State police was on patrol in a marked cruiser, traveling south on Route 1, a State highway, in the town of Lynnfield, when he noticed a Honda station wagon weaving in and out of the speed lane of the highway. He activated his cruiser’s emergency lights and caused the Honda to come to a halt off to the side of the Route 1 roadway; the location of the stop was just shy of the southbound entrance to the Lynnfield tunnel.3

Trooper Noonan left his cruiser and approached the Honda on its front passenger side. He directed the driver (the defendant) to roll down the window. With the window down, Trooper Noonan was able to detect a strong odor of alcohol from the defendant. On the floor of the rear passenger compartment, the trooper observed a bottle of Chivas Regal whiskey, approximately three-fourths empty, and a case of beer.

Trooper Noonan ordered the defendant out of the vehicle. The defendant had difficulty complying. Outside the vehicle, the defendant was quite unsteady on his feet, and conspicuously kept his left hand inside the left front pocket of his coat; he continued to do so even after being directed to place both hands on the hood of the Honda. The defendant continued to be unsteady on his feet and had to be restrained by Noonan from walking into oncoming traffic. Noonan grabbed the defendant, placed him under arrest, and removed his hand from the pocket. In the defendant’s hand was a clear plastic bag, which held five smaller clear plastic bags with a white powdery substance inside. Testing disclosed that the five small bags, combined, held 3.16 grams of cocaine.

*838Trooper Patrick Silva of the State police soon arrived at the scene with a police dog trained to alert for narcotics. Noonan had since secured the defendant in the rear of his cruiser and thereafter transported him to a nearby barracks for booking. Meanwhile, Silva had the defendant’s vehicle impounded and towed to a location off the highway where he conducted a search of the vehicle. Inside the vehicle was the defendant’s wallet, which, in its billfold, had two open bags containing small amounts of white powder, later determined to be cocaine; the two bags, combined, weighed .14 grams. No other narcotics were found.

The vital question for the jury was whether the defendant had possessed the cocaine with the intent to distribute, as charged in the complaint. In its case, the Commonwealth called Troopers Noonan and Silva, as percipient witnesses; Trooper Brian Robert, who testified that, when the defendant was stopped, he was within 1,000 feet of a school zone; and Trooper James Bruce, who was assigned to the Essex County drug task force, as a nonpercipient narcotics expert whose qualifications are not contested.

The sole defense witness was the defendant. He was then forty-nine years of age. He flatly denied having an intent to distribute cocaine to anyone.

Trooper Noonan testified that, after the stop, he had removed from the defendant’s hand the five “baggies” containing a white powdery substance, which he believed to be cocaine due to the manner of its packaging. Each bag, he recounted, had consisted of a corner torn from a plastic sandwich bag, which was “twisted” and “knotted” shut, containing cocaine with a street value of about forty dollars.4

The narcotics expert, Trooper Bruce, testified as to the street trade for cocaine. He explained that cocaine is commonly packaged, sold, and bought in the form of “small twist bags” that *839contain one-half to one gram apiece. He opined that the five glossine bags of cocaine were consistent with distribution, and that the two open bags in the billfold of the defendant’s wallet were consistent with personal use.5 Bruce testified that a half-gram bag could yield between “8 to 10 individual lines” (or “dosages”) of cocaine for a user to inhale. He concluded the five twist bags were “for sale” because the total amount of cocaine therein (3.16 grams) was “a lot of cocaine to be using all at once.”

Evidence as to the school zone was also introduced and admitted in the Commonwealth’s case. The defendant moved for a required finding of not guilty when the Commonwealth rested, and again at the close of all the evidence. The judge denied both motions.6

Discussion. A motion for a required finding of not guilty is allowed if the evidence of the Commonwealth is insufficient as a matter of law to sustain a conviction for the offense at issue. Commonwealth v. Salemme, 395 Mass. 594, 595 (1985). Mass. R.Crim.P. 25(a), 378 Mass. 896 (1979). We apply the Latimore standard: namely, in considering the Commonwealth’s evidence in its entirety and in the light most favorable to the Commonwealth, we inquire whether any rational fact finder could have found all essential elements of the crime beyond a reasonable doubt. Commonwealth v. Latimore, 378 Mass, at 677-67S.7 See Commonwealth v. Renaud, ante 261, 262 (2012). The elements for the crime here are (1) knowingly or intentionally possessing the illegal substance (i.e., cocaine), and (2) doing so with the specific intent to distribute. Intent may be inferred from the surrounding facts proved at the trial provided any such inference is reasonable. Commonwealth v. Gollman, 436 Mass. *840111, 116 (2002). Commonwealth v. Clermy, 37 Mass. App. Ct. 774, 778, S.C., 421 Mass. 325 (1995).

The defendant does not contest the adequacy of the evidence as to the element of possession; rather, on appeal, he challenges the sufficiency of the evidence as to the element of intent to distribute.

We consider “only the evidence introduced up to the time that the Commonwealth rested its case, and the defendant first filed his motion[] for [a required finding of not guilty].” Commonwealth v. Kelley, 370 Mass. 147, 150 (1976).8 “[I]t is not enough for the appellate court to find that there was some record evidence, however slight, to support each essential element of the offense.” Commonwealth v. Latimore, supra at 677. No element of the crime may be left to a jury’s guesswork or surmise. Commonwealth v. Rivera, 460 Mass. 139, 141 (2011). The evidence will be insufficient to support a conviction if it merely “pil[es] inference upon inference or conjecture and speculation,” Commonwealth v. Mandile, 403 Mass. 93, 94 (1988), or if it tends “equally to support either of two inconsistent propositions.” Commonwealth v. Rhoades, 379 Mass. 810, 817 (1980).

Consistent with the foregoing principles and based on the evidence in the Commonwealth’s case-in-chief, we are persuaded that no rational jury could have found beyond a reasonable doubt that the defendant was guilty of possession of cocaine with an intent to distribute without employing speculation or guesswork.

The defendant possessed 3.16 grams of cocaine in five twist bags. As for the remaining trace amount of cocaine in two open bags, the Commonwealth concedes that it was for personal use. The police had stopped him for a motor vehicle infraction on Route 1 in the vicinity of Lynnfield.9 The time was 9:30 p.m. on New Year’s Day. He was drunk. No exchange or transaction was witnessed.

*841The cocaine possessed by the defendant is not of an amount that alone may raise an inference of an intent to distribute, nor does the Commonwealth so contend. Compare Commonwealth v. Ellis, 356 Mass. 574, 578 (1970) (fifty-six bags of heroin); Commonwealth v. Bongarzone, 390 Mass. 326, 344 (1983) (300 pounds of marijuana); Commonwealth v. Pratt, 407 Mass. 647, 652-653 (1990) (forty-four bags of heroin); Commonwealth v. Gill, 2 Mass. App. Ct. 653, 656-657 (1974) (“hundred some-odd” bags of heroin). Nor was there anything distinctive or unique about the five twist bags to indicate they were intended for transfer or sale as opposed to personal use. More probative evidence (i.e., “indicia” or “plus factors”) was needed in order to allow a rational trier of fact to find, beyond a reasonable doubt, that the defendant intended to distribute cocaine. In other like situations, when a relatively small amount of drugs was at issue, the “Commonwealth could rely on the presence of various items used to manufacture or distribute drugs.” Commonwealth v. Roman, 414 Mass. 642, 645 (1993). “Each instance of a prosecution for possession with the necessary intent has its own singularities, which makes precedent a somewhat imperfect guide . . . .” Commonwealth v. Sendele, 18 Mass. App. Ct. 755, 758 (1984).

“[Tjhere are a number of indicia that have been considered in the assessment of the intent to distribute,” Commonwealth v. Montalvo, 76 Mass. App. Ct. 319, 327 (2010), including but not limited to distinctive packaging indicative or suggestive of distribution; possession of large quantities of drugs; the presence of implements or paraphernalia indicative of the drug trade; and the “presence of cash in combination with pagers or other accoutrements of the drug trade” found on the defendant. Ibid. See Commonwealth v. Maillet, 54 Mass. App. Ct. 910, 911 (2002). No such indicia were present or introduced here.

The Commonwealth’s evidence was not only “ambiguous,” but it also lacked specificity as to intent. Commonwealth v. Andrews, 49 Mass. App. Ct. 201, 204 (2000) (2.73 grams packaged in eleven envelopes “does not, without more, clearly tend towards showing an intent to distribute”). The defendant possessed no accoutrements of the drug trade. He had no cash. Nor did he have a cellular telephone, beeper, or pager. He had no scale or other *842measuring device. Furthermore, he was driving a vehicle on a highway and plainly not loitering in an area known for drug transactions.

The Commonwealth relies on the opinion testimony of its narcotics expert to meet its burden of proof. A qualified narcotics expert is permitted to offer an opinion based upon a hypothetical “grounded in facts in evidence, as being ‘consistent with’ a drug transaction.” Commonwealth v. MacDonald, 459 Mass. 148, 162 (2011). Initially, the expert here improperly made a direct unequivocal comment as to the defendant’s guilt, by testifying, “But the number of bags here? I would say they’re offered for sale.”10 As to the five twist bags, the expert compounded the error by stating, “that’s a lot of cocaine to be using all at once.” 11 Later, on direct, the prosecutor posed a hypothetical:

“Trooper, based on your training and experience, if, for example, there was cocaine that was approximately four grams, packaged in seven different packages, with a street value of approximately $300, where the items were kept separately and where the items were kept in a pocket, do you have an opinion of if this is more consistent with distribution or personal use?”

“Hit’s a component of each,” the expert opined, “it’s personal use and also the distribution.” A close reading of the expert’s testimony reveals his opinion hinged on critical assumptions: namely, a user would not consume 3.16 grams of cocaine “all at once” or over the course of a day, and thus, a user buying *843this amount, everyday or regularly, must be selling. Bruce testified that “a couple $40 bags every day can run into some money” and “if you get ten [bags] because you only were going to use three over a couple of days by selling those seven you’re getting free cocaine.” His testimony is wholly speculative. It was mere conjecture that the cocaine was to be used all at once or to be sold. There was no evidence that the defendant was buying cocaine, of any amount, every day or on a regular basis.12 Nor was there any evidence that the defendant was in want of money to buy drugs. He was gainfully employed. And, by altering the material facts — i.e., purchase ten bags and use three — the expert offered the jury a web of assumptions that had no evidentiary connection to the defendant.13 The trooper’s opinion was premised on facts that he had gratuitously assumed and conjecture drawn from an insufficient evidentiary foundation, and, as such, his opinion was inherently flawed and legally incompetent. With this deficient evidence, the jury were left to speculate as to the defendant’s intent.

The expert testimony also had a not-so-subtle pernicious aspect. The expert flatly described “anyone” (including the defendant) using 3.16 grams of cocaine as an “addict.” The end served by identifying the defendant as an addict before the jury was to bring a more general and insidious charge that this was a man of dangerous criminal propensities, who, because of those propensities, was more likely than not to sell cocaine. The law forbids the Commonwealth to endeavor to fasten guilt upon a defendant by intimations of his character predisposing him to a *844criminal act. “The defendant’s character was not in issue and, as all agree, could not have been used to show criminal propensity.” Commonwealth v. Kozec, 399 Mass. 514, 525 (1987). We believe “any view of the Commonwealth’s evidence, however favorable, still requires a leap of conjecture with respect to [an] essential element[] of the crime charged in order to obtain a conviction.” Commonwealth v. Latney, 44 Mass. App. Ct. 423, 426 (1998). See Commonwealth v. Merry, 453 Mass. 653, 663 (2009).

Conclusion.14 On the count of the complaint charging possession of cocaine with intent to distribute, the judgment is vacated. So much of the verdict as finds the defendant guilty of the lesser included offense of possession of cocaine is to stand; the remaining portion of the verdict (with intent to distribute) is set aside. The case is remanded to the District Court for resentencing on the lesser included offense of possession of cocaine.

On the count of the complaint charging a school zone violation, the judgment is reversed, the verdict is set aside, and judgment shall enter for the defendant.

So ordered.