The X-Series earmuffs are 3M's latest advancement in hearing conservation. New technologies in comfort, design and protection all come together in this groundbreaking earmuff line. The X3A Features: a newly designed spacer to help improve attenuation without the need for a much larger cup or double cup design. This lightweight earmuff is designed for protection against high-level industrial noise and other loud sounds. It Features: an electrically insulated wire headband, often referred to as ""dielectric"".