220V LED Flasher

This is a 220V LED flasher circuit which is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing. This a cheap circuit and easy to build.
Schematic diagram:

Component Parts:

R1_________ 100K
R2,R5______ 1K
R3,R6______ 470R
R4_________ 12K
C1_________ 1000µF 25V
D1-D4______ 1N4007
D5_________ SCR  P0102D
Q1_________ BC327
Q2_________ BC337
SK1________ Female Mains socket