... , vibration sensor, shadow sensor or rocking switch.Main component: speaker, PCB, IC, batteries, switch, wiresSpeaker available: 40mm, 29mm, 27mm,21mm ... card for example)Step 1: take out the transparent sheetStep 2: tear down the yellow paperStep 3: stick on the greeting ... set up in 1996, more than 4 years experience dealing export business.2. We are a well known manufacturer in electronics field ...