Just a little bit more to add.
If your wiring to the unit is adequate, a standard 10Amp fuse will suffice.
The other feature the fuse has is the thermal rupture (blow), of which is rated at 71 Celcius. It will also blow on reverse polarity.
Generally a 10 amp standard fuse, like what is installed in the back of the unit is fine in most applications, just ensure the polarity is correct. As others have pointed out it is to assist with protecting possible inadequate vehicle wiring; or owner wiring.