Christmas table centerpieces often feature a glass globe. It's important that candle flames are enclosed, as Christmas greenery can turn dry if used for extended time and you do not want a fire hazard. Most chimneys or globes are a standard size, where the bottom measurement is the same so they can be used in chimney picks.
The globe just snaps firmly into place into the pick.
When someone looks down from the top, you'll see that it is centered and will look good and straight once the arrangement is complete.
A side view shows the globe is well seated and doesn't tip or lean to the side. The chimney can be removed if needed to insert a fresh candle later.
I like for candles to be protected by chimneys for safer burning, but keep out of reach of small children since the glass can still get hot from a burning candle.