dbmtb":1f18db9h said:04 means it's a DH4 4 pot caliper.
They were made with interchangeable halves dependant on what size rotor and what standard fittings you had. Each half is designated with a number - for example, a 3 half is for 185mm front or 160mm rear IS. Further down on the protruding extended part below the calipers, there should be engraved a number.
What size rotor did you run up front?
From the photo it looks like it may well be a 3.