Yeah, it is the sum of the passive attenuation of the earplug and the noise masking. We don't have the test equipment yet to make a dB calculation of NRR for th

Yeah, it is the sum of the passive attenuation of the earplug and the noise masking. We don't have the test equipment yet to make a dB calculation of NRR for the foam component, but from subjective tests when comparing with other earplugs, the foam seems to block out about ~30dB!