How on/off device with relay with pulses from Arduino?

Hello.How on/off device with relay with pulses from Arduino?I want use timer 555 and mosfet...external...any simple circuit?

Why do you want to use a 555 timer and MOSFET with a relay?!?

What, exactly, do you want to do?

I want control my ac or dc device permanently for long time on or off the digitalWrite(pin,HIGH)with delay after is for little time seconds, permanently.So i think i must use mosfet,ic 555 like touch button on/off for this...the Arduino is good for pulses...outputs...

Get a dual-coil latching relay with 5V coils that draw less than 40 mA:

Connect the two coils to two Arduino pins. One will turn the relay ON permanently. The other will turn the relay OFF permanently. No power is needed to keep the relay in position. The contacts can handle 2A at 250 VAC or 220 VDC.

For higher current (10 A) you could try this one: