3M™ PELTOR™ Earmuffs X1/ X2 Probed Test Cushions easily snap into the 3M™ PELTOR™ X-Series X1 and X2 Earmuffs (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 employee's personal attenuation rating (PAR) when wearing 3M™ PELTOR™ X-Series X1 and X2 earmuffs.