Candle Tubes/sleeves cream Drip Plastic 39mm x 85mm p Smaller Dimension is the INTERNAL dimension
Light bulbs should not touch the rim of the candle tube but have a couple of mm clearance, internally we do not recommend a tight fit.
If you are uncertain how to measure your lamp holder for your tube fitting please click this link
https://youtu.be/lRqbWe7-rq8