Depends on if your amp has fuses on it. I have 4 30amp fuses on my amp...if I was to put an inline fuse before the amp...they still use the fuses on the amp to determine class. Bigger amps usually don't have fuses so you have to use inline. So if your doesn't have fuses, you can do that. Just be prepared to change fuses if your going to be using that small of fuse.