3M E-A-Rfit Dual-Ear Enclosure Assembly Speaker works with the 3M E-A-Rfit Dual-Ear Validation System to help employers determine whether workers are receiving adequate protection from their hearing protector. The enclosure assembly speaker is compact and easy to set up.3M E A Rfit Dual Ear Enclosure Assembly Speaker is a compact size and offers easy set up. It is designed for use with the 3M E A Rfit Dual Ear Validation System, which helps employers verify whether the worker is receiving adequate protection from their hearing protector. This objective fit testing system provides a personal attenuation rating (PAR) for each worker. In just seconds, it administers a test across 7 standard frequencies, quickly reporting whether their hearing protectors (earplugs, banded, or earmuffs) are effectively blocking the individual worker from potentially hazardous workplace noise. Once every employee’s personal attenuation rating is known, health and safety professionals can utilize this data to enhance their hearing conservation program.