| Where major bits are 
    affixed to an EPS foam board, be they fin boxes, foot straps, mast bases, etc, 
    such bits need to be anchored in such a way as to remain attached :) and do 
    so without leaking. The hardware, or inserts, that are installed in the 
    boards for this purpose are almost exclusively made from some reinforced plastic or another, 
    inexpensive to manufacture to reasonably close tolerances. Only problem is 
    that the Epoxy used to hold the board together does not bond to plastic 
    well. Which is why manufacturers mold some sort of ridged tooth design into 
    the perimeter of these inserts, in order to achieve a mechanical connection. 
    With EPS foam having the holding power of a marshmellow (and that's an 
    insult to the marshmellow), some sort of intermediate medium needs to be 
    introduced. Enter Divinycell PVC foam, or high density Urethane foam. 
    Surrounded by such structural foam, we can safely ignore the fact that the 
    Epoxy still will not bond to the face of the insert, since it does securely 
    bond to the closed-cell foam immediately adjacent. 
    Time and time again I find leaking and/or loose inserts 
    to have been installed without the benefit of such cartridge of structural 
    foam. Maybe, an insert destined to support a water bottle can safely be 
    installed directly into the EPS. Maybe. But anything that will see bigger 
    loads will need extra support! 
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