Choosing shaft flex without guessing

Flex is how much a shaft bends through the swing. Matched to you, the face arrives square and the ball launches on a good line. Mismatched, you fight it every shot.

Start with speed

• Under 70 mph driver speed: L (ladies).
• 70 to 80 mph: A (senior).
• 80 to 95 mph: R (regular).
• 95 to 110 mph: S (stiff).
• Over 110 mph: X (extra stiff).

Then look at your ball flight

• Ballooning, high shots that hook: the shaft may be too soft.
• Low shots that leak right and feel dead: it may be too stiff.
• A quick, aggressive transition often suits a firmer shaft than speed alone suggests; a smooth tempo, a softer one.

Weight matters too

Two shafts with the same flex label can feel completely different because of weight. Lighter shafts help speed; heavier ones help control. That's why trying them on a launch monitor beats reading labels.

Not sure of your speed? Carry distance is a rough guide: about 2.3 yards of driver carry per mph of swing speed.