This part is nearly always hard and brittle and will scratch your furniture. Either that or simply missing. As long as your candlestick is a genuine model this should fit perfectly. In fact it won't even need to be glued in. However if you prefer a couple of drops of super glue will hold it.
To fit just make sure you remove the old one properly to leave a nice clean slot. I have been meaning to get these made for years and never got round to it.