This circuit calls more Free Running Multivibrator work resemble Flip Flop. Which encourage itself repeatedly. The Q1 and Q2 be Transistor PNP be usable general (2N3906,2N2907, etc.) The R1 and R2 limit current that flow through LED the bilateral. If enhance the value C1 and C2 the rate something Flasher slow down. Request friends have fun LED Flasher , this please sir.