The Caldwell Youth E-Max Pro Earmuff has low-profile design for uninterrupted cheek weld and a compact folding design. It features easy to use push button volume controls with an illuminated on and off indicator. These earmuffs also have auto-shutoff after 4 hours without touching controls. They run on 3 AAA batteries which are included. These earmuffs are also compatible with Caldwells Rechargeable Lithium-Ion Battery Pack (sold separately).