What you need to know is that there is no standardization or regulation of NRR (dB reduction) ratings. Basically the manufacturer can list what ever amount of reduction they want. Muffs that fit comfortably and have soft rings that will seal well against the side of your head will give you the best protection. Ideally, foam earplugs worn under electronic muffs are the best. The muffs will give you some amount of amplification to overcome the earplugs, but gunfire will be muted by the muffs and the plugs help to add around 5dB NRR or so to the protection of the muffs. Where you run into trouble is if you are wearing glasses (eye protection is very important also). The temple pieces of the glasses break the seal of the muffs and reduce their effectiveness, hence why I like to wear earplugs under my muffs. Comfort and fit is number one, NRR is not really an important factor when comparing models. Sorry...Audiologist soapbox rant off. Good luck.