I found the Carbon Fiber 1" Bolt Knob to be smaller than expected and a bit undersized for my Remington 700 Tactical AAC-SD rifle. Additionally, it did not really speed up bolt cycling times or provide overall better grip.
After installing and cycling the bolt several times, I removed it and reinstalled my after-market oversized bolt knob. A 1-1/2" or 2" round bolt knob would be preferable.