In deciding this matter we once again deal with questions involving the sufficiency of a warrant which have produced such extensive case literature in recent years. The defendant was tried before a judge of the Superior Court on six indictments charging violations of the narcotic drug law, G. L. c. 94. A pre-trial hearing was held on his motion to suppress evidence obtained by means of a search warrant on the grounds that the application for the warrant did not contain facts sufficient to constitute probable cause, that the warrant authorized a general search, and that the affidavit supporting the application for the warrant did not describe the contraband sought. The motion was denied, an exception was taken, and following trial the defendant was found guilty on all indictments save one alleging conspiracy to violate the narcotic drug law. We consider whether the search made pursuant to the warrant was in violation of G. L. c. 276, § 2B, and the Fourth and Fourteenth amendments to the Constitution of the United States.
The application for the warrant was made by a Province-town police officer on the standard form on March 14, 1968, and alleged that probable cause existed to believe that certain narcotics were concealed and might be found in the possession of the defendant in an automobile registered to one Katherine M. Yon Utter of Greenwich, Connecticut. Attached to the application, explaining the source of the applicant’s belief that probable cause existed, was the following affidavit. “1. Information received from a confidential informant who is an admitted user and is known by me personally to associate with convicted narcotic users, and the informant admittedly associates with convicted users, who have past convictions for narcotic violations, and who has a user’s knowledge of narcotics. 2. Information received by me from Detective Robert Silva, who has information from a reliable informant as to dates of parties and names of persons in attendance to conform with the same type of information received from my confidential informant. 3. And information received from State Police Connecticut Narcotics Agents, Trooper Hall and Trooper Reynolds that *599John Joseph Von Utter is known to associate with convicted narcotic users. 4. Information from my confidential informant that John Joseph Von Utter will be operating a white VW 2 door sedan, Connecticut registration JJVU in Provincetown sometime between March 8-10, 1968 and will be containing a quantity of Marijuana, a Narcotic Drug and a quantity of Hallucinogenic Drug known as LSD (lysergic acid diethylamide). 5. All of the information received by me from my confidential informant has been confirmed by Narcotic Agents of the Massachusetts State Police and Connecticut State Police regarding the reputation of John Joseph Von Utter and the cars owner and description, color registration number.” The warrant was issued from the Second District Court of Barnstable on the date of the application and a return was made on March 16, 1968, which described seizure of an inventory including marijuana, pills, pipes and vials on that day from the automobile described in the warrant.
The defendant now challenges the affidavit, alleging that it lacks a recitation of sufficient basic facts, that it is not clear whether the unidentified informant “spoke with personal knowledge or in turn received this information from someone else,” that the affiant assuredly did not speak from his own personal knowledge, that the warrant was issued four or five days after the defendant was supposed to arrive in Provincetown, that there was nothing in the affidavit to indicate the reliability of the informant, and nothing to indicate that point of time when the affiant received his information from the informer.
We refer to certain basic principles. “The establishment of probable cause does not require evidence necessary to justify a criminal conviction.” Commonwealth v. Cuddy, 353 Mass. 305, 308. Commonwealth v. Lillis, 349 Mass. 422, 424. United States v. Ventresca, 380 U. S. 102, 107. However, the affiant must produce more than a mere statement of belief. He is required to set forth the underlying circumstances which produce the belief. Commonwealth v. Dias, 349 Mass. 583, 584. Commonwealth v. Cuddy, supra, *600at pp. 307-308. G. L. c. 276, § 2B, as amended through St. 1965, c. 384. Aguilar v. Texas, 378 U. S. 108, 114. If the application lacks underlying facts, information and circumstances, and indication of the source of the applicant's information or personal knowledge, the warrant is invalid. Commonwealth v. Rossetti, 349 Mass. 626, 632. Commonwealth v. Penta, 352 Mass. 271, 274. Lee Art Theatre, Inc. v. Virginia, 392 U. S. 636, 637. Hearsay may be relied upon to establish probable cause. Commonwealth v. Lillis, supra, at p. 424. United States v. Ventresca, supra, at p. 108. Furthermore, information provided by one who is a potential codefendant of the person to be searched may be relied upon to establish probable cause, Commonwealth v. Lepore, 349 Mass. 121, Commonwealth v. Lillis, supra, at p. 424, United States v. Ventresca, supra, at p. 108, as well as information coming to the affiant from police sources. Commonwealth v. Penta, supra, at pp. 275-276. Compare Commonwealth v. Rossetti, supra. The designated source of the information must be sufficiently described to enable the individual issuing the warrant to make the threshold determination of probable cause. Aguilar v. Texas, supra, at p. 114. Upon these rules as stated is superimposed the application of common sense. The saving language of the Ventresca case illuminates the proposition that, where an affidavit is not purely conclusory, reviewing courts should be slow to jettison warrants which lack “elaborate specificity.” Every effort should be made to draft each application in accordance with constitutional and statutory requirements but the rigors of an average criminal investigation are not to be intensified by a pecksniffian attention to noncrucial detail on review. Basic constitutional rights are not abraded by such an approach in the review of warrants.
In this instance, the officer who was the applicant received his information from an informant who admitted to the use of drugs and who was known to the affiant to associate “with convicted narcotic users.” The informant had had “a user's knowledge of narcotics,” a phrase capable of broad interpretation. The applicant further received in*601formation from a named fellow police officer on which he was entitled to rely who had in turn information on the “dates of parties and names of persons in attendance” which conformed to the information which his confidential informant had given to him. The distinction between the facts in the Rossetti case and those before us is that in this case the source of the hearsay police report is named and the information thus elicited tends to corroborate what the initial informant had already advised the applicant. It places no strain on the magistrate issuing the warrant to conclude that the “parties” referred to had to do with drugs rather than birthdays. The confidential informant gave specific information which tended to place the defendant with the car containing marijuana and LSD (which was ultimately searched in Provincetown) between March 8 and 10, 1968. The connection of the defendant with convicted' drug users was confirmed by certain Connecticut State Police narcotics agents, who were named in the affidavit, and the description of the car was further confirmed by them, as well as by unnamed narcotics agents of the Massachusetts State Police. We are not impressed by the defendant’s argument relative to the time lag from March 10 to March 16, when the search was made. The language of the affidavit indicates that an estimate of the arrival of the defendant with his wares in Provincetown was being made by the applicant. To hold the applicant to the statement of a day certain relative to searches such as this would be to approach the absurd.
In short, it is our view that the judge did not err in viewing the language of the application sufficient to validate the warrant which was issued. The defendant has argued strongly the similarity between the affidavit here and that in United States ex rel. Rogers v. Warden of Attica State Prison, 381 F. 2d 209 (2d Cir.), wherein a warrant was held invalid in that “it did not contain a statement that the informant spoke from personal knowledge when he reported that . . . [the defendant] was selling drugs in his apartment, nor was any information presented from which the magistrate might properly have inferred that this was so.” *602P. 217. Here, although there is no assertion of personal knowledge on the part of the unnamed informant, who correctly prophesied the descent of the defendant upon Prov-incetown, named law enforcement officers are cited as knowing themselves that the defendant associated with narcotic users and apparently attended parties involving drug violations. We view this corroboration as sufficient explanation of underlying circumstances to distinguish this case from the Rogers case and to justify a finding of probable cause by the magistrate.
On January 27, 1969, three weeks after argument of this case, the Supreme Court of the United States decided Spinelli v. United States, 393 U. S. 410, and the defendant’s counsel has since urged upon us that the Spinelli case is dispositive of this one in favor of the defendant. He has called to our attention certain similarities in the affidavits. In the Spinelli case the affidavit related a history of surveillance of Spinelli’s activities, all of them innocent enough by themselves, and stated that Spinelli was known to the affiant and to Federal and local law enforcement agents to be a gambler, a bookmaker, and an associate of bookmakers and gamblers. This latter assertion was characterized by Mr. Justice Harlan for the majority as “a bald and unil-luminating assertion of suspicion that is entitled to no weight in appraising the magistrate’s decision.” Finally, the affidavit concluded, “The Federal Bureau of Investigation has been informed by a confidential reliable informant that William Spinelli is operating a handbook and accepting wagers and disseminating wagering information by means of the telephones which have been assigned the numbers WYdown 4-0029 and WYdown 4-0136.” The majority opinion stresses that the magistrate was given no reason in support of the conclusion that his informant was “reliable.” In the present case, however, the affiant knew his informant to be a user of drugs and an associate of convicted users of narcotics. Here there exists a strong likelihood that the informant, a longtime drug user, would be thoroughly familiar with the sources of supply. It was reasonable to rely *603on information furnished by such a drug user. In the Spinelli case the court distinguished the fact situation of Draper v. United States, 358 U. S. 307. In the Draper case the informer did not state how he obtained his information but stated that Draper had gone to Chicago “the day before by train and that he would return to Denver by train with three ounces of heroin on one of two specified mornings.” The informer described with particularity the clothes Draper would be wearing on his return. The court then said, “A magistrate, when confronted with such detail, could reasonably infer that the informant had gained his information in a reliable way.” In the present case the informant described with particularity the car which the defendant would be operating in Provincetown, giving its registration, its contents, and an estimated time of arrival. We are of opinion that the Draper facts are more closely similar to those in the one at bar than the facts in the Spinelli matter. As Mr. Justice Harlan has pointed out, while the Draper case “involved the question whether the police had probable cause for an arrest without a warrant, the analysis required for an answer to this question is basically similar to that demanded of a magistrate when he considers whether a search warrant should issue.” We conclude that the affidavit in the present case is not invalid under the Spinelli decision.
Exceptions overruled.