Pyramex's Venture Gear Sentinel Electronic Earmuff features slim profile ear cups, fold-away, padded headband, and a front facing microphone. The muff helps amplify hearing, while compressing harmful sounds and reducing them to a safe level. It also has an auto shut-off after four hours, 3.5 mm AUX jack for use of MP3 and mobile devices, and height adjustment to fit all sizes. Brand Pyramex Category Hearing Protection Model Venture Gear Series Sentinel Color Powder Blue Ear Cups w / Black Band Material Polymer Style Over the Head Battery AAA NRR 26 dB