Valentine's Day Gift - Red and Pink Blinking Love Heart Necklace 12 Pack Valentine's Day Gift blinking heart necklaces are great accessories for all celebrations, festivities, and occasions. They're made of plastic material and feature multi-colored blinking LEDs. Each box contains 12 heart necklaces. Non-replaceable batteries are included and installed. To start the light, press the center of the heart and it will start flashing. Hearts measure 1.5 inches. Not for children under the age of 3.