Goes through the instrument with a suitable degree of resistance. Doesn't seem like it's going to break any time soon, unlike the swab which came with my Startone clarinet, where the weight fell out of the fabric after a few months.
Important safety tip: Swab from barrel to bell and make sure the cord and swab have no knots before inserting them into the instrument! Otherwise the swab might get stuck in the register tube - luckily you can get it out by pulling on the cloth without damage, as long as you swab from barrel to bell.