Project X EvenFlow, HZRDUS or HZRDUS Smoke Shafts w/ Adapter Tip for Ping Drivers - Installed. Instead of the standard flex designations such as Stiff and Regular, etc., they use a numbering system. In it's simplest form, the 5.0 designation is for Senior Flex, 5.5 equates to Regular, 6.0 is Stiff and 6.5 is Extra Stiff or "X" Flex.
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