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Players cited with this
Brooks KoepkaPRESS“The 30-year-old has been an equipment free agent for a number of years now, and up until very recently has been playing exclusively with Mizuno’s JPX series irons.”
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Players who use this also use

Mizuno JPX 919 Tour irons
also used by 2 of them

Srixon ZX4
also used by 1 of them
Srixon ZX7 irons
also used by 1 of them

Srixon ZX7 MK II
also used by 1 of them

TaylorMade SIM Max
also used by 1 of them
Titleist CB 714
also used by 1 of them
Photo credits
- Brooks Koepka — Idz93, CC BY-SA 4.0