https://thegreatmodel8.net/

I saw a post talking about a Md 8 at an auction and they said it was a "Round Knob", as though it was something unique. Can somebody enlighten me. Thank you.

This is what I would call a "round knob" Model 8. It's a type of rounded shallow pistol grip style stock.

Sir,
The round knob model 8 is considered a highly desirable type of rifle ,to those of us who collect model 8/81s. This type of stock was designed after the Auto 5 shotgun and Fn1900 rifle. I don’t know if this was a JM Browning design or if it was created by someone at FN. It’s also possible though,that someone at Remington created it. The dates of when they all started into production, are all very close together. Nonetheless,they are sought after by people like me.
So I believe that they are somewhat special.
Roger

I'm inexcusably late thanking the two fellows who answered my question. Thanks to both.