Basic question here: what is a "Russian" strop, and how does it differ from a "non-Russian" cowhide strop? (I'm talking here about how the strop is made, not country of origin.)

Some information sources tend to suggest that the two are the same, whereas others suggest that this isn't the case (and that a Russian strop is a kind of love-it-or-hate-it sort of affair).

Thanks.
-Ivan