Could Someone Verify That This Relay Diagram Works?

i have tried implementing the following relay diagram and it does not appear to work or my test is faulty. Could someone please verify that it works - also a little confused by the little black rectangle with the white line (between pin 87 and 87a) i'm assuming that's the coil as no mention of any other component was listed (outside of a capacitor and a resistor).

here is the relay diagram in question:
https://www.the12volt.com/relays/relaydiagram44.html

Thanks

https://www.the12volt.com/relays/relaydiagram44.html

Yes it works. But it will not work without the Diode that is between 87 and 87A

1000 microfarad capacitor and a 10,000 ohm resistor is what the diagram states. Are those the values you used?

Yes those are the values i used. So is this as simple as buying a relay with a diode in it already and then hooking up the rest of the wires?

If so, do you recommend one or would any 30amp relay with a diode work?

Here is how i had it hooked up today (will this be the same with the new relay or do i need to do something with pin 87a )?

pin wire color     location
87 - green           to neg of cap and resistor

87a - blue           not used

30 - black           to neg output (this is where i expect to see 1/2 second ground pulse)

85 - white           to positive of cap and resistor

86 - red             to 12v power supply

87 to negative of cap and to resistor and also to ground.

A relay with an internal diode will work. Or any 1 amp diode 1N4001, 1N4002, 1N4003,or any through 1N4007 will work as well.