Dimensions for Drill Hole to Install Mounting Panel for Redarc Tow-Pro Elite Brake Controller Knob

Published 06/07/2019

Question:

What is the diameter of the round part that is inserted in the panel? Not including the LED notch or the gripping pieces not the 1-1/8inch shown in the pictures. This would be the minimum size hole to drill in any panel on any vehicle prior to cutting out the LED notch section to ensure a snug fit so it wont spin in place since it would be held in place by the LED section of the switch.

asked by: Pete

Expert Reply:

The outer diameter of the smallest round part of # 331-TPSI-003 is 1-1/16 inches. That's not counting the tabs or the beveled section and is shown by the red arrow. I think that's what you're asking about. If not let me know.

With that being said at the top of that is a notch that makes it so the hole you drill may need to be larger. From top to bottom with the notch it measures 1-1/8, just like the tabs, and is shown with the yellow arrow.

expert reply by: Charles S