No products in the basket.
How to Choose the Right Insert Normally, fitting a round tube insert is simple: you measure the outside diameter of your tube (so the head of the cap sits completely flush with the outer wall) alongside the wall thickness.
However, if your tube has an unusually thick wall, standard matching might not work. This calculator is designed specifically for those non-standard situations. Instead of matching the outside diameter, you can use this tool to find a cap based purely on the internal hole diameter (the bore).
Please note: When sizing based on the internal hole of a thick-walled tube, the head of the chosen end cap will be smaller than the outside diameter of your tube. It will not sit flush with the outer edge, but it will fit the hole securely.
⚠️ Important: Tube Inserts vs. Hole Plugs Please do not use these ribbed tube inserts as blanking hole plugs for thin sheet metal or flat panels.
Our plastic end caps feature flexible ribs (lamellas) around the shank.
These ribs are engineered to compress and grip against the inner depth of a tubular section.
If fitted into a thin sheet, the ribs will not have sufficient surface area to grip onto, resulting in a loose fit that will easily fall out.
