DHC-100 The helix on some of the ‘06 and newer Arctic Cat models with the new ACT secondary is now a cast / one-piece version. We still use our same billet helixes as we did on the first direct drive models. In order to use the billet helix on these models it is necessary to use a helix cap from a ‘04 - ‘05 Arctic model with the ACT secondary (and associated hardware) or this Dalton Billet cover. This kit, part # DHC-100, comes with a billet cover, complete with bushing and the necessary hardware to install our billet “C” helixes on newer versions of the clutch. Only one kit is necessary as it can be transferred to any Dalton “C” helix you choose for future tuning.