UPDATE: The verdict is in. . . .
Today, I cut open one of the filters from the six I purchased from Amazon. When I began this endeavor, I didn't have specific things in mind to look for other than "uneven filtration media pleats and less media overall" (which one website said would be an indication of a counterfeit filter). I ended up noting other important characteristics that I found to be relevant to this issue.
After cutting the filter I began a close examination of the individual components and made the following observations, the sum of which convinced me that
this was, in my opinion, an authentic OEM MOBIS-made Hyundai filter, that I'll use in my Hyundai vehicles without further concern. In my examination, I payed close attention to quality of materials, fitment, smoothness of edges and any markings on the internal / external parts.
Here are my observations, in no particular order:
--the steel (canister) shell is very rugged, obviously thicker than many other filters I've used. Using digital calipers, I measured the thickness of the shell at .75 mm. The canister was clean, smooth and had no slag or other contaminants within.
--The ADBV is very pliable orange silicone and has three marks molded into it-- "SC" , "K68" and the Hyundai "H" emblem. It should be noted that these marks are extremely small and wouldn't have been noticed without the zoom lens feature of my phone / camera.
--The spacer that separates the filter media from the dome of the shell is very strong (not easily flexed) steel that fits perfectly into the dome without any lateral movement when in place.
--The steel spacer is stamped to fit into a recessed area in the aluminum top of the filter media and fits perfectly at that point.
--The steel spacer has NO sharp edges and has a shiny, smooth finish.
--The filtering media unit has yellow paper-like material folded in fairly even, closely spaced pleats, comparable to materials I've seen in other filters. The filter media is capped on two sides by aluminum discs and held in place by glue (some of the glue is visible (see pics). There are no visible holes or tears in the media or pleats.
--The media unit internal tube is made of spiral-designed aluminum, with multiple circular holes cut therein, allowing visible access to very closely spaced media pleats.
--Inside the media unit the bypass valve spring housing is visible, with the Hyundai "H" emblem stamped facing the open end of the filter.
--On the dome-end of the media unit, there is a hole in the aluminum through which a white, plastic "button" is visible. That plastic button can be depressed, and is likely being held in place by a coiled spring. The pressure against the plastic button is substantial and requires some effort to depress it.
--The vertical measurement between the two aluminum discs measured (with digital calipers) between 51.25 mm and 51.47 mm (or about 2"), measurements being taken in several places around the outside edges of the discs. The media unit is symmetrical and fits closely and evenly to the edges of the canister shell.
--On the open end aluminum disc of the filter media unit there is stamped in blue ink the following date: "2019.08.14"
--The mounting plate is made of very thick, heavy steel and has a black, rubber gasket securely affixed to it. This gasket has "SC" , "ACM" as well as the Hyundai "H" emblem molded into it.
--The mounting plate threads are smooth to the touch and appear shiny and of good quality
--Mounting plate inlet holes are uniform and smooth on both sides of the plate with no sharp edges.
Reasoning: This filter is apparently well-designed and made of quality materials and of good finish inside and out. While exterior (visual) features are usually exploited by counterfeiters, it's unlikely that the quality interior fit, finish and appearance would be so completely duplicated in such an endeavor. In addition to the build features, there are certain marks on internal parts of the filter that are a good indicator that the parts are authentic, to wit, the date stamp (2019.08.14) on the filter media unit which coincides with the claims by the vendor that the filter is of a recent design and part number change (would a counterfeiter put a date stamp INSIDE a sealed filter?). Also, the presence of the (almost invisible) molded Hyundai "H" emblem present on the silicone ADBV (internal) and rubber gasket (external) would unlikely be exploited by a counterfeiter--most people (except BITOGers) wouldn't cut open a perfectly good filter to look for trademarks.
The only things I didn't do (yet) in my examination is weigh the parts--I don't have an accurate scale in the weight range of the filter. . . and I didn't measure the area of the filter media (didn't think it was necessary). If anyone needs this info, let me know and I'll try to get it done.
Questions, comments, criticisms? --Rob