IC555 Pulse Timer Control Relay Circuit and explanation

Today we would like to offers solutions for a set time for take control relay and take NO. / NC. contact to apply to control other devices . such as disable or enable the device.
function of this circuit is using IC555 to determine the pulse and a resistor R1 to the period of time.
R1           #Seconds
100k         2
220k         3
470k         6
1M           15
The increase provides more time to increase the value of the Capacitor.

Electronic Part List
R1 = 1 Meg, Preset Pot
R2 = 10K  
R3,R4 = 1K
C1 = 10uF, 16V
C2 = 0.01uF
T1 = BC547 (Gen Purp NPN)
T2 = 2N2222 (Hi Current NPN)
D1 = 1N4001 (Gen Purp Si)
IC1 = 555 (Lo-Power version)
RLA1 = Relay, 9V (amps of your choice)