I've been working on various circuits to make LEDs (12 volt clusters of them) strobe. I looked at a commercial unit. It does not use a 555 because pin 1 is the 12v voltage in on the 8 pin IC. Pins 2 and three have a 64K resistor across them. Pin 4 is not connected. The output (PIN 7) looks like it connects to one side of a transistor. The center pin and I assume it the BASE connects directly to the output (12 volts). The circuit will drive up to 100 leds it says. It strobes (4 times in a second) pauses and repeats. Any help on what the IC number and transistor type would be appreciated.