Cap Back Design | How it Works and What It Does for Your Game

Looks, feel and performance. These are vital factors our engineers consider when developing a new iron. Rarely do you find a piece of tech that enhances all three, but that's the case with Cap Back™ design on the all-new SIM2 Max and SIM2 Max OS irons.

To develop this tech, the team asked themselves one question:

"What would happen if we supported the entire topline from heel to toe?"

Finding that answer meant looking back at Speed Bridge's breakthrough performance in prior gen irons. First introduced in M5 and M6 irons, it linked the topline and the backbar using two connection points, effectively forming a bridge across the iron's cavity back. That design impacted feel by helping reduce vibrations at impact. It helped generate distance and faster ball speeds by working in unison with the Speed Pocket on the club's sole. Finally, it created a wow-factor with its unique look.

So, if SpeedBridge did all of that with just two connection points…what would happen if the entire topline was supported and connected to the backbar?

Thanks to Cap Back design, we now have the answer to that question. Made from a lightweight composite material, it spans the entire cavity and better secures the topline and delivers additional rigidity in the face's upper part. In conjunction with the flexible Thru-Slot Speed Pocket™, it creates a larger unsupported area of the face, which translates to improved flexibility engineered for increased ball speeds and distance. That added flexibility made it possible to deliver the prominent, more intelligent sweet spot.

We know what you’re thinking. “Intelligent sweet spot? Really?” While these irons may not have a Ph.D., some of the people who designed them do. They charted data from thousands upon thousands of golf shots and determined the iron face's most common impact points. Surprise, surprise - golfers don’t always hit in the center. But where do they miss it the most? Data shows high toe and low heel are the hot spots. So, our engineers strategically shaped and positioned the sweet spot to capture more of those areas.

This was all made possible by Cap Back design.

That covers feel and performance, but what about looks? The layered carbon composite gives the iron a clean and distinctive look that will stand out in your bag. It delivers a similar aesthetic to the carbon driver crowns TaylorMade has been known for in recent seasons.

Now that we’ve gone through a quick overview, let’s dive deeper into the technology.

Traditionally, iron construction has been divided into two fundamental categories: 1) High-COR cavity back with low CG. 2) Forged player’s iron with lower COR but excellent workability and superb sound and feel. Firstly, what is COR? It stands for Coefficient of Restitution and basically reflects how energy is transferred when two objects collide – which makes it extremely important when developing irons. With the introduction of the forged P•790, TaylorMade introduced a new classification of irons that was able to blend the COR of a cavity back with the look and feel of a player’s iron.

In 2021, Cap Back fuels the next performance leap by utilizing the concept of the hollow iron, but replacing the steel back with a composite covering, attached to a new optimized topline with a specialized damping layer that lowers the center of gravity and provides exquisite sound and feel.

The technology combines the traditional performance benefits of cavity backs with the characteristics of players' distance irons, such as P•790 and P•770 forged irons. By integrating the composite material onto the back structure of the iron head, engineers are able to achieve the high COR and optimal mass properties of the cavity back design, and match it with the clean look, sound and feel benefits of a hollow players' distance iron. This is not simply taking aspects from two constructions and placing them in a single iron, but unlocking improved performance in all aspects by utilizing this new technology.

Cap Back dramatically increases the COR area while optimizing the back portion of the head for mass efficiency. A forged hollow players' distance iron, such as the P•790 and P•770, is able to achieve the elevated performance over a traditional players' iron by fully enclosing the back while leaving the inside open for increased COR. This back section of the head provides stiffness for improved sound and feel, but also comes at the cost of added weight, raising the center of gravity. In the case of the P•790 iron, this back portion of the head accounts for over 17g of mass, and even with low-profile tungsten weighting, the P•790 still has a slightly higher CG than the SIM2 Max iron.

The optimized, lightweight and composite Cap Back design is able to provide the stiffness, as well sound and feel improvements, of a hollow body iron while also significantly reducing mass – therefore making it possible to achieve an optimal center of gravity for forgiveness and launch.

Harsh vibrations that can interpreted as poor sound and feel in an iron stem from two primary sources: 1) The thin face flexing and “ringing,” or oscillating, after impact. 2) The topline bending and flexing, which creates a loud, lower frequency that is often referred to as “clack.” Cap Back, in conjunction with the next generation ECHO® Damping System, minimizes face vibrations and really shines when it comes to mitigating the lower frequency topline vibrations.

Because Cap Back is directly applied to the topline, and stretches all the way across, it helps damp out those vibrations at the source. In addition, the fundamental design of the feature is a stiffer, more mass efficient configuration that vibrates less, leading to a premium sound and feel that is unmatched in game improvement iron.