One Iron Golf Pro-Line Single Length Clubs Collection 8 Iron Set
1 Iron Golf Pro-Line Wedges Collection GW, SW, LW
1 Iron Golf Pro-Line Irons on White background
One Iron Golf Pro-Line Full 11 iron set
Pro-Line Specifications Chart for One Iron Golf
One Iron Golf Pro-Line Single Length Clubs Collection 8 Iron Set
1 Iron Golf Pro-Line Wedges Collection GW, SW, LW
1 Iron Golf Pro-Line Irons on White background
One Iron Golf Pro-Line Full 11 iron set
Pro-Line Specifications Chart for One Iron Golf

Pro-Line Irons

Regular price $699.00 Sale price $489.30

Shipping calculated at checkout.

Since we custom build all orders, please allow 7-10 business days for your order to ship. For questions, please contact us. Thank you!

Precision Tooling, Shaft Balancing, and Club Stability for the ultimate in Precise Shot Making.

Based upon the proven clubhead design of our original 1 Irons, we designed the Pro-Line for the next-level golfer looking to maximize distance without compromising accuracy. This iron line is modeled after touring irons, incorporating the design features that professional golfers prefer: lighter clubhead weight for added swing speed, 2º stronger loft angles for a more penetrating ball flight, and a stiffer shaft tip section for enhanced stability through impact. 

Maximize your distance without compromising accuracy.

  • Custom Built: Custom fitted based upon your wrist-to-floor measurement (see below for measurement instructions). Identical club length, clubhead lie angle, swing-weight and (MOI), and shaft flex throughout the set.
  • Clubheads: Tour proven clubhead design. 2º stronger loft angles throughout the set for increased distance. Lighter clubhead weight for increased swing speed and distance. Deep undercut rear cavity produces and extremely low COG for maximum trajectory and distance. State of the art precision casting, grinding, and polishing. Latest groove technology for maximum back-spin.
  • Shafts: Steel shafted for the highest level of consistency/accuracy. Shaft flex plane orientation (Spine Align/Puring). Optimized shaft tip section for extreme stability through impact and tighter shot dispersion.
  • Grips: Installed with oversized grips.
  • Available in Right and Left Hand
  • Conforms with the Rules of Golf.
  • Built in the USA by Master Club Builders.

Shop the Pro-Line Combo Sets and Used/Demo Pro-Line Iron Sets.

Custom Fitting Single Length Irons

All human beings share the same skeletal, muscle, tendon, and joint functions and from a mechanical standpoint are the same regardless of height or sex. Non-mechanical differences arise in custom fitting however, for instance: the height of a bicycle seat needs to be greater for a taller person than a shorter person even though the mechanical design of the bicycle remains the same. By the same token there is only one true fitting variable in the building of golf clubs and that is club length. Based upon your wrist-to-floor measurement we adjust your club length to correspond to the lie angle of our club-heads in order to ensure a proper fitting.

Wrist-to-Floor Measurement
Taking your Wrist-to-Floor Measurement:
  • The wrist-to-floor measurement should be taken while standing on a hard surface.
  • Wear jogging/gym shoes (not golf shoes) not in excess of 1.5" sole.
  • Stand with your back against the wall at strict military attention. Place your shoulders and head against the wall, your feet together, and your arms rigid and straight down at your sides.
  • Hold a pencil in your right hand (right handed golfer). Back your arms against the wall and then take the pencil and make a mark where your left wrist joint hits the wall. Just the opposite for a left-handed golfer.
  • Measure from this mark to the floor.
  • Important: Do not round-up the measurement to the next higher inch increment. For instance, if your measurement is 34 and 7/8″, do not round up to 35″.

One Iron Golf Club Lengths

One Iron Golf Club Lengths - Wrist to Floor Measurements

Very Important:

Do not order based upon what you consider to be your favorite iron (ie: #7 iron), and do not use that corresponding wrist-to-floor measurement when placing your order. When ordering you need to specify your actual wrist-to-floor measurement to ensure a proper fitting. This chart reflects club length based upon our club-head lie angles. Consequently, our fitting process does not apply to any other brand.

For the taller golfer:  based upon your wrist-to-floor measurement you may be concerned that your irons would be a typical #3 or #4 iron club length; however, do not compare your measurement to your current #3 or #4 iron. The lie angles of your “long” irons are much flatter than ours which, at your size, requires you to bend over excessively and reach out for the ball at address. The club head lie angle of our irons is 63.5º which is far more upright and allows you, for the first time, to stand upright and much closer to the ball at address resulting in the ideal upright swing posture and swing plane. The taller golfer benefits the most from our fitting formula since they have never played golf clubs that have even come close to fitting them properly. The result being that they have had to develop a very inefficient posture and swing where they are bent over excessively and reaching way out for the ball with every iron in the bag.

How Does the Wrist-to-Floor Measurement Work?

It is based upon trigonometry. At the point of ball impact in the downswing, your wrist, the ground, and the club-head, form a right triangle. Assuming an ideal swing posture, there is a non-linear mathematical relationship between your wrist-to-floor measurement while standing at attention and your wrist-to-ground distance at ball impact.

The club-head lie angles are known for the irons and fairway woods as well as the length of one side of the right triangle based upon your mathematically factored wrist-to-ground distance at impact. This gives us the measurement of two angles and the length of one side. We then use trigonometry to solve for the hypotenuse or club length. This is somewhat oversimplified as we factor in shaft deflection and numerous other factors. The fitting formula that we developed produces the ideal golf club length for anyone regardless of height or arm length.

Why Conventional Custom Fitting Does Not Work


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  • You will receive an email from us with your tracking number.
  • Ohio residents will be charged 7.25% sales tax.

International Ordering

  • Free International Shipping on all purchases over $1,000 USD.
  • We ship worldwide and we cover the brokerage/clearance fees.
  • Import duties and taxes are the responsibility of the customer and will be collected by the carrier at time of delivery.
    • If these taxes are not paid your order will be shipped back to us and we will deduct from your refund the cost of shipping both ways and the import duties/taxes charged to us.
    • Not sure if you will need to pay import duties and taxes? Check with your local customs office for estimated duties/taxes, or use this link for an estimate in your currency.

Return Policy

Fully try-out our golf clubs at your home course and at your convenience for a full month. We feel that to truly evaluate a set of golf clubs to determine if they are right for you takes time; and hence, our 30-day return policy (does not include Used/Demo golf clubs, Accessories, or Special Orders). To our knowledge we are the only golf club manufacturer in the entire industry who offers a full money-back return policy on golf clubs after they have been played which should tell you volumes about our commitment to our customers.

If you are not completely satisfied you may return your golf clubs within 30-days of receipt for a full refund of your original purchase price (no hidden fees or re-stocking charges). A return authorization must be obtained before we can accept a return of merchandise. Contact us for this authorization on-line through the Contact page of this website. Shipping/handling charges are not refundable. All contents listed on the original Packing Slip must be included for a full refund. Return shipping charges are the responsibility of the customer. Our return policy is only valid once per customer. Any alterations to the original golf club voids this policy.

If shipping from outside the USA make sure to show that the country of origin is the USA and is a return of USA manufactured goods on the customs form. Also, be sure to make clear that you (the shipper) are responsible for all shipping charges and any brokerage/storage/handling/duties and taxes incurred. We will not accept any return package where a payment is due - the shipment will be returned to you at your cost. Any charges incurred by us will be deducted from your refund.

Order Cancellations

If you cancel your order prior to it being shipped your refund will be subject to all credit card processing fees assessed which will be deducted from your refund. If you cancel your order after it has shipped you will have to return it to us at your cost. Once we receive the returned order your refund will be subject to all credit card processing fees assessed plus our shipping cost to you which will be deducted from your refund.

Limited Warranty

We warrant our golf clubs to be free of defects in material and workmanship for a period of one year following the original ship date. We will, without charge to the original purchaser, repair or replace the club if it proves to be defective during normal use within this period (normal use does not include misuse or abuse and the associated damages ie: dents on the top, side, rear, or sole of a wood club-head). This does not cover grip or cosmetic wear and tear due to normal usage. Any alterations to the original golf club voids this warranty.

Customer Reviews

Based on 29 reviews
Mark D. (Cedar Rapids, US)
All good

Quick & accurate

Steve m. (Cheyenne, US)
Great Irons

I have used the Pro-Line irons for a little over a year. Easy to hit, accurate and consistent. Maybe proof could be my latest outing hitting to the green, from the rough, about 175 yards out, hitting my 5 iron and ball stops on the green 3 feet from the pin. This has been the results always straight at the target. Looking forward to seeing how the driver and fairway woods will work.

Donald J. (Amelia, US)
Pro line

The quality of the clubs is very good. Great grips, good balance. I like the white lines on each club. It’s a heavy club. Heavier than the clubs I play, Mizuno. Still working with the One Irons. pretty big learning curve for sure. Good clubs.

Bryan M. (Auckland, NZ)
Bryan Matthews New Zealand

Purchased proline irons handicap went down 4 places accurate yardage between
irons now interested in a set of regal irons.5 star rating for company service.

trent d. (Des Moines, US)
As expected

I've had them for about two year
They're solid. They do what I need them to do. They do as advertised
I think the price point is high considering how "boring" they are
Boring function - no shaft options (can't even put blackstone shafts into pro-lines), no grip options, can't adjust loft or lie, zero customization. I also think they are behind the technology curve but they state it hasn't changed in 20+ years... I'm just not sure if I believe their marketing
Boring looks - furrels are ugly and come loose right away, paint job is ugly but holds up well
Ultimately, you get what you expect... 20+ year old technology and style

Kevin H. (Lawrenceburg, US)
3 iron

Definitely my go to club for more distance on long par 3 and all my get out of trouble stinger shots,absolutely love it 😍,1 iron golf for life!!!

Paul O. (Chicago, US)
Pro-Line irons hard to launch

Purchased the irons and had trouble hitting them after numerous trips to the driving range.. The clubs look great, but the grips are hard and I had trouble launching them very high compared to my old Cleveland irons. I had high hopes for these irons but decided to return them.

Mike C. (Indianapolis, US)

Absolutely love my irons.

Bryan H. (New Orleans, US)

I love my irons, one simple swing , I'm shooting in the 70's more often now. It's hard to break 80.

Ken W. (Torrance, US)
Totally satisfied customer 😀

I've played 5 rounds with my pro-line irons, and I'm totally pleased with them. I love the feel of these irons. I've been playing golf for 30 years and have owned 7 sets of irons, and these pro-lines are by far the best. I purchased the 3 thru PW, and I'm going to order the SW, GW and LW. These irons feel like butter, and the distance that I'm getting is amazing. I wish that I would have gotten these irons years ago!