... PCB, IC, speaker, microphone, LED indicator, batteries, plastic shell (more or less for different items)Power : Button cell AG13 AG10, Dry ... and sound, customized sounds are available (MP3 or WAV format file )Function: pre-recorded or recordable, USB input, with LED flash ... The OEM solution service as follow:Customer's design or idea----Product blue print----YDL coordinates with strategic partners ...