Shafts
Driver shaft flex by swing speed
ELDRICK picks driver flex from your measured driver speed: Senior up to 77.9 mph, Regular from 78 to 91.9 mph, Stiff from 92 to 103.9 mph, Stiff+ from 104 to 107.9 mph and Extra Stiff from 108 mph. A fast tempo paired with a quick transition moves you up one flex, and nothing moves you below your speed band.
| Driver speed | Flex | Fast tempo and quick transition |
|---|---|---|
| 62 mph or less | Ladies for women, Senior for everyone else | One flex up |
| 62.1-77.9 mph | Senior | Regular |
| 78-91.9 mph | Regular | Stiff |
| 92-103.9 mph | Stiff | Stiff+ |
| 104-107.9 mph | Stiff+ | Extra Stiff |
| 108 mph and up | Extra Stiff | Extra Stiff |
A slow tempo with a smooth transition can't drop you below your speed band. Women have their own Ladies line: Ladies at 71 mph or less with the driver.
What ELDRICK fitted, by driver speed
- Senior
- Regular
- Stiff
- Stiff+
- Extra Stiff
The 90-99 mph Regular share is mostly golfers at 90 to 91.9 mph, still inside the Regular band.
Why speed decides flex
Flex is about how much the shaft bends and kicks back during your swing, and club speed is the simplest measure of how hard you load it. So ELDRICK brackets flex on the speed you produce today, measured with your current club.
That last part matters. If your driver is too short for you, ELDRICK credits you up to 6 mph of extra speed for the longer club you'll be fitted into (2.5 mph per inch of shortfall). That credit feeds shaft weight. It never moves driver flex, because the speed isn't real until you swing the new club.
Tempo can move you up, never down
Golfers with a fast tempo and a quick transition load the shaft harder than their speed alone suggests, so both together push you one flex firmer. A smooth, slow swing gets a lighter build elsewhere, but flex stays at the speed band's floor.
Fairway woods and hybrids use this same ladder at each club's own speed, which is lower than your driver's. That's why a golfer in a Stiff driver can land in a Regular 5-wood. See fairway wood vs hybrid.
Irons use a different ladder
Iron flex reads 7-iron speed: Senior up to 69.9 mph, Regular from 70 to 81.9 mph, Stiff from 82 to 88.9 mph and Extra Stiff from 89 mph. The stiff vs regular guide covers the boundary golfers ask about most.
Frequently asked questions
What flex should I use at 90 mph driver speed?
Regular. ELDRICK fits Regular from 78 to 91.9 mph. If you have both a fast tempo and a quick transition, it moves you to Stiff.
What flex is 100 mph swing speed?
Stiff. ELDRICK fits Stiff from 92 to 103.9 mph, or Stiff+ with a fast tempo and quick transition.
When do I need an extra stiff driver shaft?
At 108 mph driver speed or more, or from 104 mph with a fast tempo and a quick transition.
Does ELDRICK fit women differently?
Yes. A woman gets Ladies flex at 71 mph or less with the driver. Women aged 67 and up still get Ladies up to 3 mph over that line. Above it, the standard ladder applies, never below Senior.