what is this?

[Revracer]

so what all would i need? just some caps and wire? if i have a spare 470uf 16v cap(pulled it off an old esc when the esc crapped out. dont know if its still good...) would that be fine? what about the novak mega that is like 8200uf? or the 4700uf one. if i could make one for like $10 or so should i? and what do you mean run it in line with your deans? like solder it onto your battery connector?