If you’re doing your own routine maintenance—and if you’re not, why not?—you’re going to need a means to open your canister oil filter after every oil change. There are choices on the market, and each design seems to follow a slightly different philosophy, even if the desired result is much the same: Cut the base end off the metal filter body so you can examine the paper filter media.
One complication in our world is that there are basically three kinds of filters, including the small, spin-on style for Rotax engines that more resembles motorcycle filters than conventional aircraft pieces. Of the two remaining, there are differences in spec, whether they have an internal bypass or not and in overall length. But the one difference of most interest here is whether the filter has a male thread extension or a female equivalent to thread onto the oil-filter adapter. The male version is more common among Lycoming engines (typified by the 48110 part number), while Continental tended toward the female style (the 48108). What’s more, several aftermarket adapters, like the one on my Titan IO-340, use the version with the stud on the engine, not the filter.