Where to get 300lb and 500lb dumbbells?

Hello,



I would like to get a pair of both 300 and 500lb dumbells, preferbally "cheap" or used. Does anyone out there know who makes these or where to get some? Any help would be nice!


Thanks



I didn't find the right solution from the Internet



References:

forum.bodybuilding.com/showthread.php?


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