Most business cards are printed on stock that's pretty close to 0.5mm. In reality there's no gap between the boot and the AFD when the skier is standing in the binding as the boot will be hard down on the AFD. But that then means that there's a 0.5mm gap between the top the boot toe lug/welt and the underside of the toe wings - which is need for a smooth snag/friction free lateral release.
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