Hi BD
Can I use the Radius UFO silent cap on a standard silent burner?
Signed, Silent Guy

Nope. Sorry, Silent Guy. A lot of people don’t realize that there is a size difference between the two types of burners. The Radius “Special Silent” burner is substantially smaller than the standard #5-sized silent burner.

“Special Silent” on the left, standard #5 sized burner on the right

If the spigot tube on the “Special Silent” (aka the UFO burner) looks smaller than the #5 spigot tube, that’s because it is. The “Special Silent” spigot tube has an outer diameter of 14.5mm while the OD on the #5 burner is 16mm. So, no way the UFO cap will fit on the #5 burner.

If you have not got a #5 burner in hand, here’s how the “Special Silent” compares to a standard sized #1 roarer burner. Hope that helps. BD