the fuse question can be answered by a previous post here ... just look down a bit ... as for which ohm sub u want it depends on your amp, check the specs of your amp and then see where it can run the most power, eg if it runs 400wrms at 4ohm get the dual 2 ohm and run it in parallel, ie 2+2=4ohms. if it runs 400wrms at 2ohms then get the dual 4 ohm since 4+4 in parallel = 2ohms ... simple physics ... slightly more complicated if u want to run more than 1 sub .. and yeah nice choice of sub