Understand your shaft. Play your best golf.

Guide · 4 min

Which Autoflex is right for me?

The SF Series has five models — each tuned to a specific CPM frequency and weight. The fastest way to find your model is your driver swing speed.

Model	Weight	CPM	Swing Speed
SF305X	37g	170	Under 70 mph
SF405	46g	190	70–85 mph
SF505	50g	210	85–95 mph
SF505X	54g	220	95–105 mph
SF505XX	58g	240	105+ mph

Don't know your swing speed? Any driving range with a launch monitor can measure it for free in under five minutes. It's the single most useful number to know before buying any shaft.

The purple rows are the most commonly fitted models — SF405 and SF505 together account for the majority of Autoflex fittings worldwide. If you're unsure, start with SF405 if you're under 85 mph, SF505 if you're 85–95 mph.

Every SF shaft is frequency-matched to ±2 CPM during manufacturing — tighter than any conventional shaft in the same price range. The model you order is the model you receive.

Explore the full SF Series →

Guide · 5 min

Autoflex vs. Autopower — how to decide

Both lines use KHT carbon technology. The difference is how that technology is applied — and which type of golfer each is designed for.

	Autoflex SF	Autopower
Weight	37–58g	50–75g
Flex feel	Very active, KHT-forward	Familiar, conventional feel
KHT placement	Full shaft	Strategic mid/tip zones
Best for	Golfers open to a new feel	Golfers who want gradual transition
Fitting method	CPM-based	Standard flex grades (R/S/X)

Choose Autoflex SF if:

• You want maximum distance from lighter weight
• You're comfortable with an active, loaded feel through the swing
• You swing under 105 mph and want CPM precision fitting
• You've been told your current shaft is too heavy

Choose Autopower if:

• You want KHT performance without leaving conventional feel behind
• You're transitioning from a brand-name OEM shaft
• Your swing speed is above 85 mph and you want more stability
• Your fitter recommends starting with a heavier option

Compare Autopower models →

Guide · 6 min

Reading launch monitor data with KHT

When you put a Dumina shaft on a launch monitor for the first time, the numbers often look different from what you expect. Here's how to read them correctly.

Higher launch angle — this is good

KHT shafts load through the mid-section and release at impact, which raises the dynamic loft at the moment of contact. Most golfers see +1° to +2° of launch compared to their previous shaft. Unless you're already launching too high, this translates directly to more carry distance.

Lower spin — but not dramatically

The lighter weight and lower torque profile of KHT tends to reduce backspin slightly. For golfers who were spinning the ball too high, this is a benefit. If your spin drops below 1,800 RPM with a driver, talk to your fitter about a slightly stiffer model.

Ball speed often stays the same or increases

This surprises most golfers. A lighter shaft should theoretically produce the same ball speed with less effort — or more ball speed with the same effort. The 10-gram rule: every 10g reduction in shaft weight adds roughly 1 mph of clubhead speed, which translates to ~1.5 mph of ball speed and ~3–4 yards of carry.

Metric	What to expect	If it looks wrong
Launch angle	+1° to +2° vs. previous	Over 16° — try stiffer model
Backspin	Similar or slightly lower	Under 1,800 RPM — go stiffer
Ball speed	Same or higher	Lower than previous — recheck shaft length
Smash factor	1.45–1.50 target	Under 1.42 — check face contact
Dispersion	Tighter left-right	Wider — tempo mismatch, refit

Learn how KHT works →

Guide · 3 min

Caring for your Dumina shaft

Dumina shafts are built to last — but high-modulus carbon requires a little more care than standard graphite. Follow these guidelines to protect your investment.

Adapter torque

When installing or reinstalling with a hosel adapter, torque to 40–45 inch-pounds maximum. Over-torquing compresses the tip section and can micro-crack the carbon layup near the hosel — damage that isn't visible but affects CPM consistency over time. Use a torque wrench, not a hand-tight guess.

Regripping

• Use a standard grip solvent — mineral spirits or commercially available grip tape solvent
• Pull the grip straight off, never twist-and-pull which can stress the butt section
• Avoid heat guns near the shaft — high heat can soften the resin matrix in the tip section
• Double-sided grip tape is fine; avoid thick wraps that change the effective grip diameter significantly

Storage and transport

• Never leave your bag in a hot car — sustained heat above 60°C (140°F) can soften the epoxy bond at the hosel
• Use a bag with individual club dividers to prevent shaft-on-shaft contact during transport
• Avoid leaning shafts against hard edges — high-modulus carbon is strong under flex but can chip if struck sharply at a point

Cleaning

Wipe down with a damp cloth after each round. Avoid abrasive cleaners or steel wool on the shaft finish. For paint fill in the graphics, a soft toothbrush with mild soap keeps the lettering clean without scratching.

Support & FAQ →