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??? photon
From The re-PSUPedia
A slot, found on striking weapon boards, for any type of photon. Using photons designed for ranged (Im-photon) or TECHNIC (El-photon) weapons changes the final product to that of a lower grade and/or reduces the success rate by a significant percentage without any benefit.
All melee weapon boards accept elemental photons. This reduces the success rate by a small percentage and changes the final product's element.
Examples:
