Every term on your spec card, in ordinary English

Shaft weight

Measured in grams, and the single most influential shaft property. Weight sets the tempo of the whole club. A heavier shaft slows the transition and generally tightens dispersion; a lighter one speeds the transition and can help a player who has been fighting the club.

Common bands: iron shafts run roughly 60 to 130 grams, driver shafts 45 to 80. Moving twenty grams is a change you will feel immediately. Moving five grams is usually imperceptible outside a controlled comparison.

Frequency

How fast a clamped shaft oscillates, expressed in cycles per minute. Higher means stiffer. It is the only stiffness measurement that means the same thing across manufacturers, which is why we record it and why the printed flex letter appears nowhere on our card.

Across a set, the useful thing is not the absolute number but the slope — how many cycles the frequency rises for each club shorter. A consistent slope makes a set feel like one family. A ragged one produces the club in the middle that never feels right.

Bend profile

Where along its length a shaft is soft or stiff. Two shafts can share weight and frequency and still behave differently because one is soft in the tip and firm in the butt while the other is the reverse.

Tip-soft shafts add launch and spin, and can feel unstable to a strong player. Tip-firm shafts hold launch down and reward a player who loads the club late. Butt stiffness mostly affects how the transition feels rather than the flight.

Torque

Resistance to twisting, in degrees. Lower is more resistant. Torque affects perceived feel more than measured flight for most amateurs, and the industry numbers are not directly comparable between makers, so we treat it as a feel adjustment rather than a specification target.

Swing weight

The old alphanumeric scale — C9, D2, D4 — describing how heavy the head feels relative to the grip end when the club is balanced at a fixed fulcrum. It is not a measure of total weight. A heavy club can have a light swing weight and a light club can feel head-heavy.

One swing weight point is roughly two grams of head mass, or four grams under the grip, or a quarter inch of length. Those three levers are how we hit a number.

Counterbalance

Weight added under or near the grip. It lowers swing weight while raising total weight, which makes a club feel lighter in the hands but more stable through the strike. Useful for players who want a heavier overall club without the head feeling like a sledgehammer.

Grip core and build-up

Grips come with a core diameter that must match the butt of the shaft. Under that grip, layers of double-sided tape build the size up in measured steps. Each full wrap adds roughly one sixty-fourth of an inch to the diameter.

Size affects hand action. A grip that is too small encourages the hands to be busy; one that is too large quiets them and can leave a face open. We record the exact wrap count so the next set matches without a conversation.

Lie angle

The angle between the shaft and the sole when the club is soled flat. Too upright sends the ball left of the start line; too flat sends it right. Measured statically on a gauge and dynamically on a lie board, and the two rarely agree.

Loft

Measured, never assumed. Stamped loft and actual loft differ regularly, and forged heads drift in use. What matters on the course is delivered loft, which includes how much the shaft leans forward at impact.

Playing length

Sole to butt cap, measured with the club soled at your address position. Catalogue lengths assume a standard lie and a standard posture, so a club that reads 37 inches on a chart can measure something else entirely once it is soled the way you actually stand.

Ferrule and hosel depth

Cosmetic in appearance, structural in effect. If a shaft does not seat to the bottom of the hosel, the effective playing length and the frequency both change from what was intended. We seat to depth and record it.