3M™ PELTOR™ Earmuff Probed Test Cushion B easily snap into specific 3M™ PELTOR™ Earmuffs or Headsets (sold separately) to allow for fit testing with the 3M™ E-A-Rfit™ Dual-Ear Validation System. The complete system issues a pass or fail rating based on the workers personal attenuation rating (PAR) when wearing 3M PELTOR Hearing protectors.