First number on all of Track's bowling balls are the year it is made in, so your 7 means 1997. If you look at the GP2s, they all start with a 5, except for a very few that were released early, meaning they were produced in 2004 or 2005.
Clint
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Clint Daley-Owner
Lets Go Bowling Daley
Salem, Ohio 44460
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