to an impossibly high standard under dauber and under well settled a circuit president if there is a dispute as to the factual support for an expert's opinion the issue is to the jury poor is properly the subject of vigorous cross examination the presentation of contrary evidence and an appropriate jury instruction the factual basis of an expert's opinion goes to credibility not to admissibility only if the opinion is fundamentally unsupported the expert be precluded see for example st vs united states which is cited in our that the defendant's cause defendants product caused the injury and that there is no dispute but what the district court never considered and did not address is how the plaintiffs proves that the products cause the injury report describes this methodology as to how we identified the web slowing in question as being a granger product examined not only the web sling that examined two others one was in the mr burton did not address which was could julie the chinese manufacturer make the same wessling for others and when she found that that question had not been  answered to preclude mr britten's testimony as in this simple down tells us what to do in those circumstances conceding for the purpose of argument that there was something shaky when the four wheel drive partial or wheel drive was switched on and the expert in that case said something to the effect that well it's very well known that four wheel drive time drive vehicles are hard to handle and he never surprise surprise supply would give me any evidence for that opinion in pro service that case involves a defective space heater or can never explain why in spite of the internal malfunctions of the space ringback heater the fire how the fire reached the case which was in fact there were no holes in the outer case of the space heater ignited the rest of the building in which it has been sold so he was those are both causation question cases your honour's not a product identification questions upshot of affirming the district court's opinion in this case is that a plaintiff who doesn't have a receipt and doesn't have a clearly marked product could not simply be without recourse when injured by a product with the judge's ruling mean that you have to have a receipt or a clearly marked product couldn't you put on some other evidence the sling came from grange r it's from the company or testimony from somebody who knew d it came from the range or somebody who's involved in acquiring the slings for the employer or wages that could be proved besides a receipt  situation of your hypothetical well i'm just wondering whether the the evidence here according to the district court was was insufficient but there might be other ways to prove it summary judgment plaintiffs failed to do substantial evidence that the product or web sling was supplied by defendants other than the subjective opinion of playing up sex  which the trial court correctly deemed inadmissible d under federal rule of evidence to as amended and there was no proof of product identification plaintiffs do not dispute that the entire case rests on the admissibility of the expert's opinion regarding product identification we believe that the judgment of the district court below should be affirmed the following facts were undisputed in this case as the motion for summary judgment was heard by the district court there was no permanent an incapacity tag and warning label on the subject neither plaintiff nor his coworkers could identify who made or supplied the sleighing plaintiff's employer wyler the owner of the sling and subpoenaed under rule forty five dollars they could not produce a single slayings from other suppliers none of these slayings were analyzed by plane of expert granger searched hundreds of pages of its own records none were cautioned time and time again not to use those slings when the only proof a product was a flawed opinion by its expert brickman as the records found his opinion was based on quote unquote insufficient facts making reference to a federal rule of evidence seven o two and as a result it contains an analytical gap an expert opinion based on insufficient facts is unreliable and it didn't miss the boat and the evidence the judgment call as to what facts are deemed quote unquote sufficient to undergird an opinion rests with the sound discretion of the trial court in the proper exercise of its gatekeeping function in this case judge was well within her discretion to find the man's opinion was based on insufficient facts as the district court judge pointed out in a cogent well reasoned opinion the expert's opinion was fatally flawed in that he failed to establish a probability that the civil i think it is your honor from the standpoint that under rule forty six a summary judgment motion has to be supported and opposed ringback by admissible evidence the evidence of product identification in this case came really only from mr bergman plaintiff sexperts so the rule fifty six dollars inquiry then has to take a look at the admissibility  or data now all in all fairness some of these elements of the rule seven o two analysis don't necessarily fall into distinct categories or buckets  and i i think it's fair to say there's some overlap but her decision was based on insufficient facts and an insufficient analysis by the plan of sex for i think part of the infusion your d honor on this your to rule out other possibilities is that in the district court or the plane the expert filed a five page affidavit d to supplement his fifty five dollars report of opinions and in that five page affidavit the plaintiff sexpert said in two different locations that based on his analysis he had x glued every other possibility consider fact judge weapons your looked at looked at that affidavit and found that that analysis was based on insufficient facts and there was inadmissible an alternative round upon which th court could affirm the ruling below would be that according to the plaintiff expert's own testimony in his affidavit he was provably wrong the judge in essence proved the expert wrong by showing that there's another possibility here and that possibility is that this julie sling the company in the people's republic of china the fabricate things could have sold the slings to other people not granger and not data slings and for that reason when the expert makes the statement under oath in an affidavit that i have excluded every other possibility under the evidence he has actually blown a hole through his own opinion and that begs the question is that expert's opinion given that background on product identification a reliable d opinion under rule seven o two and under admissible within the context of rule fifty six dollars motion for summary judgment as this court knows in a product case yes you refer to whether the chinese manufacturer might have sold the slings others yes you're acknowledging that there was sufficient evidence that this plane did come from that manufacture or is that also the spirit issue no no we do not acknowledge that fact i mean that that is not a fact that is proven in this record that this particular polyester most all of these slings have internal red thread so d when the slaying is used and worn out too much it will wear through and start to show the red thread d inside that means you need to take the take the sling and and that's not the subject that would be some additional circumstantial evidence to support their claim but again we don't think it's enough evidence under rule seven o two that the expert could give a reliable and got there or where that i mean that that's just what the state of the record is d d again i think that circumstantial evidence in their favor but we think that the evidence was  by granger i understand so there is no direct evidence of that i was just wondering whether that circumstantial evidence is sufficient we don't think it's sufficient enough your honor because we think if they're proving their case by virtue of circumstantial evidence they need to show d that they are proposition is the most probable proposition under the h i see that i'm out of time unless there's any other more questions more questions thank you very much