Shimano shoe plugs

Just got my new Shimano R170 road shoes, so what are the little red plugs in the bottom of the sole for?
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Planet X RT58
Cannondale CAAD 10 2012.
Pain.. Is weakness leaving the body.
HATING LIFE-CYCLES FROM 2011
Planet X RT58
Cannondale CAAD 10 2012.
Pain.. Is weakness leaving the body.
HATING LIFE-CYCLES FROM 2011
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Are there just plugs in the screw holes or something?
Planet X RT58
Cannondale CAAD 10 2012.
Pain.. Is weakness leaving the body.
HATING LIFE-CYCLES FROM 2011
Guessing this simplifies set up options and you only remove plugs if you need a position you cannot get from cleats alone.
Most road shoes do not have a carrier that moves do they (mine do not)?
Not sure a moving carrier is necessary (maybe it is for some cleats) or a good idea, but the plugs on those seem to be just making the threads stay in one place as they would be on most (?) shoes.