Electric fuel pump relay... single pole or double pole? What's the difference?

[brads70]

I'll be adding a electric fuel pump to the Challenger this winter and was looking at relay kits. What's the difference between single and double pole? What's the difference between these two kits? ( besides the cost?)What's better and why? Electronics are so not my thing... but I'm learning!
http://www.summitracing.com/parts/PRF-30131/?rtype=1
http://www.summitracing.com/parts/PRF-50102/

[MEK-Dangerfield]

It's too early in the morning for me to explain it.   

All you need is a simple single pole design. A double pole design would leave you with 2 outputs, which you don't need here.

[brads70]

It's too early in the morning for me to explain it.   

All you need is a simple single pole design. A double pole design would leave you with 2 outputs, which you don't need here.

 Thanks Mike! Hope you went back to bed, kinda early for a Sunday Morning!

[Chryco Psycho]

Mike is right all you need a single 30 amp relay . Princess auto carries the pigtails for them .
A relay is a simply switch you use low current to power a coil to create an electromagnet to close the switch
You can get 100s of relays in the wreckers , all new cars use low current switches & relay for 10 or more circuits , I usually grab a handful when I am at the wreckers .
 relays are numbered 84,85,86, 30 & 8?A
# 30 & the terminal across from it are the high power circuit , I usually use 30 as the high power in  , the other 2 on the sides are the low power in & ground , normally you switch power to the side terminal which closes the switch & powers the accessory . The center terminal 8?a is a reverse circuit so it is constantly powered until the relay is powered turn off the circuit to the accessory