What is the red marking on the end plug of my LCN 4600, 4800, or 2600 operator?

This is just a color coding we use to identify the housing for the standard 4631, 2610, 4811, and 4840. - because these all get the spacer inside the housing to restrict the opening distance.

For an example of a 4631see here.

Important note:  The following ST special cylinders per series, will not have this Red Marking as the cylinder does not have the spacer.
4630 series - ST3096
4810 series - ST3041, 2671, 3354, and 2252
2610 series - ST1885, ST1885-1, ST1885-3, ST2962, ST2962-1, ST2962-2, ST2989, ST3032, ST3123, ST3249, ST3399, ST3458, ST3541, ST3578, ST3602, and ST3209. 

DISCLAIMER:

INFORMATION PROVIDED THROUGH THIS SITE IS PROVIDED TO YOU AS IS WITHOUT ANY EXPRESS REPRESENTATIONS OR WARRANTIES OF ANY KIND, AND WE MAKE NO REPRESENTATION OR WARRANTY THAT THIS SITE(OR ANY INFORMATION PROVIDED IN RESPONSE TO YOUR INQUIRY), WILL BE ACCURATE, COMPLETE, OR ERROR-FREE.

YOU AGREE THAT YOU MUST EVALUATE ALL INFORMATION AND RESPONSES, AND THAT YOU BEAR ALL RISKS ASSOCIATED WITH, THE USE OF THIS SITE, INCLUDING ANY RELIANCE ON THE ACCURACY,COMPLETENESS, OR USEFULNESS OF ANY INFORMATION OR MATERIALS MADE AVAILABLE THROUGH THIS SITE.