all i can assume is that they decided to change the international standard mounts in 2005
other than that i can't see any real difference in the holes on the backing plate in the photo's, check your bikes mannual or the manufactures website to see which one your bike has
ISCG is also known as ISCG-03, or what we call ISCG-OLD. It is a mounting pattern for a chainguide, and very open to interpretation. This can sometimes lead to problems. ISCG-05 is a mounting STANDARD that was agreed upon by no less than five MTB companies at Interbike in 2004. It is stronger (by design, to withstand DH use), and much better defined to eliminate any mounting issues with ISCG-OLD.
ISCG is also known as ISCG-03, or what we call ISCG-OLD. It is a mounting pattern for a chainguide, and very open to interpretation. This can sometimes lead to problems. ISCG-05 is a mounting STANDARD that was agreed upon by no less than five MTB companies at Interbike in 2004. It is stronger (by design, to withstand DH use), and much better defined to eliminate any mounting issues with ISCG-OLD.