I have the standard glass slide, but I've also found that it is easier to have a compound slide configuration , fretting with the other remaining fingers if I use a cap from my Martin's guitar polish spray bottle. It basically only covers a little more than the first joint on my little finger and allows my other fingers to bend for fretwork.

Also allowing for selective silencing. In the eighties, I used to have a half length brass ring type slide. Don't know if I still have it, Don't care. Brass is soft, easy on the strings, but does wear and will create tiny metal particles, not user friendly. Fender bottle caps work nicely also. One is longer than the other. I don't know which is which. neither are on the bottle, but in my pick cache.