Fender embelem
 

I have a 2013 300SRT8, and my brother has a 2012.
his has a 6.4 Hemi badge on his fenders , mine don't.
I looked online and most do not.
I'm thinking this is added by the owners and not the factory.
Am I right?

You're correct in your observation about the badges. The 6.4 Hemi badge on your brother's 2012 300 SRT8 is likely an aftermarket addition, as not all 300 SRT8 models came with that badge from the factory. The 2013 models, including yours, typically don’t have the badge either. It's not uncommon for owners to personalize their cars with badges or decals to highlight the engine specs or for aesthetic reasons. So, if most of the 2013 models are badge-less, it supports your thought that it’s an owner-added feature rather than a factory standard. If you're considering adding one

If most 2013 models are badge-less, that definitely supports the idea that it’s an owner-added feature rather than something standard from the factory. If you're thinking about adding a badge yourself, it could be a fun way to customize your ride and make it stand out a bit more! Just make sure it aligns with your style and vision for the car.