They're metric, so just use the one from the set that fits BEST. No sloppy fits or you'll ruin the head of the capscrew.
Should be 10mm or 3/8ths Actually, it turned out to be 7mm Allen wrench.
7MM
7mm Allen wrench
To tighten and loosen Allen head bolts
9mm Allen wrench
The caliper bolts can be accessed from the rear of the caliper. After removing the tire you can view the recessed brake caliper bolts. You will need a large Allen wrench, as these are Allen head bolts. Consult your auto parts store for the proper size Allen wrench. Common toolbox wrenches will be far too small. I would advise to spray down with some WD-40 the night before. You should also make available a large hammer to hit the wrench and loosen the bolts, as it is an akward position to muscle the bolt free with a short wrench.
7mm Allen
You need a 3/8 Allen key to release the caliper.
the front calipers take a 9 mil Allen head and the rear take a 7 mil, noth arent in your average homeowner Allen set
it's a 3/8 wrench for both 2003 and 2004 caliper.
You need a 3/8 Allen Wrench
Most likely a 15mm wrench. Unlikely to be Allen in that vehicle.