Fusible link question

[Pinchecharlie]

I purchased a Madd electric kit for my truck and iam using a junction box at the core support for relays. Iam not to electrical savvy! Anyway the instruction say to use a fusible link in line with the power source to power the relays. My question is can a fusible link be used on its own? I only have to go a few inches from power junction to relay. Kinda dumb I know but I wondered enough to call Madd (Not available as of yet) and thought I'd ask. Seems like a fail safe but didn't know if it had to do with the links length or its relationship with another wire lol! Ism not to proud huh? Thanks just trying to make it as clean as possible.

Just fyi; these Madd electric kits are really awsome and relatively affordable especially if you are like me and not allways confident with electrical wiring. The end