2) Open ski rule: Any OEM or aftermarket skis are allowed as
long as they have ISR approved loops.

3) Open track: Any OEM track for the sled brand is acceptable
as long as OEM part number is legible and lugs are of original height.

4) Larger capacity OEM fuel tanks and other OEM items that make
the machine more "cross-country friendly" without presenting an
unfair competitive advantage will be considered for approval. The item must be presented to USCC tech director prior to event for inspection.