A panel includes a front panel, a door, and a linking-up member. An opening is defined on the front panel to access an optical drive. The door is for covering and uncovering the opening. The linking-up member is slidably received in a first passage of the front panel and pivotally engaged with the door. A first resilient member is restricted between a rear side of the front plate and the linking-up member, wherein the first resilient member pulls the linking-up member inward. A second resilient member is positioned between the door and the linking-up member to pull the door inward to cover the opening. The door is pushed outward to uncover the opening when a tray of the optical drive is ejected.