Description: new and Product Description: This circuit is composed of 16 pcs LED (light emitting diode). The 16pcs LED divided into four groups, and each group has different flashing frequencies, when four groups flash together. This item looks like a little Christmas tree. the circuit is powered by a 9V battery. Advantages: This circuit is simple and practical, low power consumption.It uses integrated circuits for driving: fewer parts , and the line is simple and easy to understand. External wiring kit: with pluggable plug for easy replacement of parts at any for time and conducive circuit debugging. Also allows us to deepen our understanding of the principles of the circuit in the debugging process. This line is in the form of the oscillation circuit by the cycle generated by the following principles: -after the first charge, the capacitor C1 C4 charging is complete. -capacitors C2 C3 will continue to charge. -when the transistor Q1 Q4 is turned on at the same for time, it discharges the capacitor C1 C4. -capacitors C2 C3 is fully charged, the transistor Q1 Q4 will be closure, while also charging the capacitor C1 C4 again. -transistors Q2 Q3 is turned on while the capacitor C2 C3 will be discharged. -By analogy, the flash of speed is the oscillation frequency, and the frequency is determined by the resistor R capacitance C values. Suite: PCB circuit boards, battery box components. (No batteries) If you need the instruction, contact me, I will send you a data download link~ Board Size:70mm*110mm Quantity: 1 PC Package includes: 1 x Christmas LED Trees