I've always wondered how often the chains are calibrated...Do they shrink or expand depending on the temperature???...Do they stretch over time due to the constant pulling???...Where does the NFL buy the chains from???...Does some company have an exclusive NFL chains contract???...How often are the chains replaced???...Do they ever break???...If so, are they repaired or replaced with a new set???...If they are repaired, does some company have an exclusive NFL chain repair contract???...How much does a net set of chains cost???...Where are the chains kept between games???...Could some unscrupulous fanatic access the chains and alter their length???...What would happen if all the chains were stolen???...How much does a used set of chains cost on eBay???....(I'll go check on this right now and get back with you...
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