Shell material: high quality cold rolled steel. Electroplating guarantees colors keep shinning and bright. * Silent, no ticking to ensure a good sleep and best working environment. * Night light (built-in lamp) is perfect at night. Simply press the button when staying in bed. * Super loud alarm sound for heavy sleepers. * Notice: the two buttons to set time and alarm are designed that way. Please don"t mistake the special design for the sign that they"re broken or of poor quality.