KING F9 SPEEDBACK ONE Length Irons
The KING® F9 SPEEDBACK™ ONE Length™ irons are engineered to simplify your game by reducing variables in your swing to increase accuracy and consistency.

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What IS IT
Each ONE Length iron is designed to match 7-iron length and weighting to deliver consistent feel, trajectories and distance gapping through the set.
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WHO IT'S FOR
Ideal for 5 to 25 handicaps with moderate to faster swing speeds seeking a forgiving distance iron with great feel. ONE Length allows you to swing every iron like it's your trusty 7-iron.
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Why we made it
The Cobra ONE Length irons are inspired by the revolutionary swing philosophy pioneered by Bryson Dechambeau on Tour. A ONE Length configuration allows you to use one repeatable setup and swing through the set, resulting in more consistency and accuracy.


One Length.
One Swing.
Engineered using matching 7-iron length and weight specifications, a ONE Length configuration simplifies your game by reducing variability in your setup and swing for increased consistency.


Wider Sole Widths
Wider soles in the 4-6 irons lower the club's center of gravity to deliver hybrid-like distance, launch and forgiveness with iron-like precision.

Progressive Shaft Weighting
Premium aftermarket KBS shafts in three different weights (KBS Tour 80 in the 4-6i, KBS Tour 90 in the 7-9i, and KBS Wedge in the PW-SW) optimize launch, feel and trajectory through the set.

Speedback
Design.
Much like a wide-body kit adds to the stability of a racecar, SPEEDBACK shaping utilizes a belt of steel that adds mass low and wide, creating a lower, deeper CG that maximizes ball speed, launch and carry while maintaining a conventional sole width.

Forged E9 PWRSHELL Face
An E9 variable thickeness face design is 1.8mm at its thinnest point, expanding the SWEET ZONE to increase distance on off-center hits. A forged PWRSHELL design features a deep undercut sole with a 1.2mm internal Speed Channel that returns more energy to the ball for higher launch and faster ball speeds.

High MOI Design With Tungsten
SPEEDBACK adds more mass low and wide compared to a conventional game improvement iron. 33 grams of tungsten is combined in the heel and toe in the 4-7 iron, increasing MOI for maximum stability, higher inertia, and substantial improvements in ball speed, distance and forgiveness.

Best In
Class Feel.
A 3-piece multi-material medallion combines aluminum, TPU (Thermoplastic Polyurethane) and acrylic foam. These lightweight materials damp vibrations to promote a softer, more responsive feel that is not normally found in a game improvement iron.

CNC MILLED
FACE AND GROOVES.
CNC milling is a highly precise manufacturing method that is typically only found in forged player's irons. This process allows us to create perfectly flat faces, and precise lofts and groove shapes in every iron we manufacture.

Progressive
spin technology.
Progressive groove shapes are CNC milled into each face to optimize spin performance in the long irons, mid-irons and wedges.

4-7i
MILLED V-GROOVES
CNC milled V-grooves reduce spin for increased distance and flight time.

8i-PW
MILLED U-GROOVES
CNC milled U-Grooves optimize spin for improved control and accuracy.

GW-SW
WEDGE GROOVES
Tighter-spaced, U-grooves increase spin for improved precision around the green.
Progressive
hosel lengths.
Shorter hosels in the long irons (4-6) lower the CG to increase launch and distance, medium hosels in the mid irons (7-9 iron) create a gradual transition from the long irons and taller hosels in the wedges (GW-SW) raise the CG to promote control and accuracy.

PRACTICE SMARTER.
IMPROVE FASTER.
COBRA CONNECT grips feature embedded sensors that work in conjunction with the Arccos Caddie mobile app - the award-winning connected golf system that helps players of all skill levels make smarter, data-driven decisions and shoot lower scores.
Learn More

Automatic Shot Tracking
Receive real-time data for all aspects of your game.

True Club Averages
Select the right club for every shot with SMART DISTANCE insights.

Advanced Analytics
Use detailed performance breakdowns to guide equipment choices, practice & more.

Golf's Smartest Caddy
Trust artificial intelligence to reveal your best strategy tee to green.
CONNECT YOUR
ENTIRE SET.
With your purchase of a set of KING F9 SPEEDBACK irons, you will receive your choice of FREE additional Arccos Caddie Smart Sensors or COBRA CONNECT grips so you can connect your entire bag (from your driver to putter) and experience your first set of Smart Clubs.
Receive game changing insights FREE for 3 months, then subscription rates apply.
How to redeem:
- Purchase a set of KING F9 SPEEDBACK irons.
- Download the Arccos Caddie app on your mobile device.
- Follow the instructions through the Arccos Caddie app to redeem your FREE Cobra Connect grips or Smart Sensors.
Download Arccos Caddie:

STOCK SET COMPOSITION - 7 Clubs
- Steel: 5-GW
- Graphite: 5-GW
Iron | Loft | Lie Angle |
Offset (mm) |
COBRA CONNECT Length (Graphite & Steel) |
Standard Length (Graphite & Steel) |
Graphite Swing Weight |
Steel Swing Weight |
RH/LH |
---|---|---|---|---|---|---|---|---|
4 | 19.5° | 65.0° | 6.0 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
5 | 22.5° | 64.5° | 5.1 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
6 | 25.5° | 64.0° | 4.2 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
7 | 29.5° | 63.5° | 3.2 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
8 | 34.0° | 63.0° | 2.6 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
9 | 39.0° | 62.5° | 2.0 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
PW | 44.0° | 62.0° | 1.5 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
GW | 49.0° | 61.5° | 1.0 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
SW | 54.0° | 61.5° | 1.0 | 37.50" | 37.25" | C9 | D1 | RH/LH* |
*LH Custom Only

Model | Flex | Shaft Weight | Kick Point | Trajectory | Spin | Tip Diameter |
---|---|---|---|---|---|---|
Fujikura ATMOS 6 ONE Length | Stiff | 66g | Mid | Mid | Mid | 0.370 |
Fujikura ATMOS 6 ONE Length | Regular | 63g | Mid | Mid | Mid | 0.370 |
Fujikura ATMOS 6 ONE Length | Lite | 62g | Mid | Mid | Mid | 0.370 |

Model | Flex | Shaft Weight | Kick Point | Trajectory | Spin | Tip Diameter |
---|---|---|---|---|---|---|
KBS Tour 80 | Stiff | 100g | Mid-Low | Mid-High | Mid | 0.370 |
KBS Tour 80 | Regular | 100g | Mid-Low | Mid-High | Mid | 0.370 |

Model | Flex | Shaft Weight | Kick Point | Trajectory | Spin | Tip Diameter |
---|---|---|---|---|---|---|
KBS Tour 90 | Stiff | 102g | Mid-Low | Mid-High | Mid | 0.370 |
KBS Tour 90 | Regular | 95g | Mid-Low | Mid-High | Mid | 0.370 |

Model | Flex | Shaft Weight | Kick Point | Trajectory | Spin | Tip Diameter |
---|---|---|---|---|---|---|
KBS Wedge | Stiff | 120g | Mid-Low | Mid-High | Mid | 0.370 |
KBS Wedge | Regular | 110g | Mid-Low | Mid-High | Mid | 0.370 |