Yeah I realize where to buy the chains, I'm wondering what the stresses are that a dual 1/2" chain set up isn't as strong as a single 1" or even a single 7/8" provides. What's the physics behind it. To me two 1/2" chains would seem to be stronger than a 7/8" but that's the upgrade. So would two 7/8" chains be stronger than a 1"? I assume there is only enough room for 1" so that wouldn't be feasible. Is it that the stock chains are made inferior too? Could the Gemini design be fixed and made stronger. Maybe I worded my question better this time.