The DM line from Crescendo offers four color-coded models, each with a different level of strength for protecting the ear against damage from high-decibel music. Options include black (25dB), white (20dB), blue (15dB), and green (10dB). The DM plugs incorporate DEC filter technology that offers flat attenuation. As a result, music is brought down to a comfortable volume level while maintaining an even frequency range.

 
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