This get the job done but their quality it's not really consistent for every piece. I bought 7 of these for a recording session, two of them couldn't be used because they were too tight and i couldn't fit the headphone jack in, one of them was wobbly when inserted in the jack socket of the headphone preamp and sometimes it worked and sometimes not.
They just aren't that reliable, but they are really cheap so you can just buy more and hope they work.
Also they age really fast, the rubber wears out visibly in less than a year.