Ben Hulka
Ben Hulka helps players and fellow caddies each week on the PGA Tour by selling yardage and green contour books for each course produced by former caddie Mark Long.

Yardage and green contour books are a staple at PGA Tour events. Players and caddies alike depend on these tools as they do everything they can to contend in tournaments week in and week out.

But unlike the average Joe playing at a local course who purchases a yardage book in the pro shop for $5 before a round, the ones out on the PGA Tour are far more detailed. So much so, in fact, that former caddie Mark Long has made a business out of it. Long maps out all the courses on Tour in extensive detail — especially the greens.

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Long then sends the yardage and green contour books to the event where caddie Ben Hulka sets up shop Monday, Tuesday and Wednesday of tournament week to sell them for $150 (with a $50 credit to those who turn in the book from the previous year). That right there should tell you just how valuable they are.

The Caddie Network caught up with Hulka to learn more about how it all works.