Does Coco Gauff play with a stock Head Boom?

No, Coco Gauff does not use a stock Head Boom. Her racket is a highly customized Pro Stock model with the internal code PT374.1. It features a custom carbon layup, lead tape placed in the hoop, and silicone injected into the handle to match her preferred weight and balance.

What is the head size of Coco Gauff's racket?

Coco Gauff uses a 100-square-inch head size. This head size offers a forgiving sweet spot and helps her generate easy depth and power, especially when chasing down difficult balls on defensive slides.

How heavy is Coco Gauff's strung racket?

Coco Gauff's customized strung racket weighs approximately 325 grams (11.5 ounces). While this is lighter than the heavy frames used by many male pros (which often exceed 340 grams), it is significantly heavier and more stable than the retail Head Boom MP model.

What strings and tension does Coco Gauff use?

She strings her racket with Head Hawk Touch 17g (1.25mm) polyester strings at a tension of approximately 55 pounds (25 kg). This setup provides excellent control, durability, and spin to tame her rapid, whip-like baseline swings.

Is the Head Boom suitable for intermediate players?

Yes, the retail Head Boom MP (295g unstrung) is highly recommended for intermediate club players. It offers a large sweet spot, comfortable feel, and easy access to power and spin, making it a very user-friendly 'tweener' frame.

Coco Gauff Racket Setup: Custom Specifications

Since winning her first Grand Slam title at the US Open, Coco Gauff has established herself as one of the most athletic and formidable competitors on the WTA Tour. Her game is characterized by extraordinary court coverage, lightning-fast defensive slides, and a backhand wing that can redirect pace with absolute, surgical precision. To support this highly dynamic baseline game, Gauff relies on a meticulously tuned racket setup engineered by Head.

While she is the global face of the Head Boom racket line, touring professionals rarely play with stock rackets straight off the retail shelf. Instead, they use customized frames tailored to their physical needs, swing speeds, and sensory feedback. In this comprehensive guide, we will break down the exact specifications of Coco Gauff’s customized racket setup, detail the custom engineering behind her pro-stock frame, and explore how these specifications impact her performance on the court.

1. The Paintjob Myth: Pro Stock vs. Retail Models

To understand Coco Gauff's racket, one must first understand the concept of "paintjobs" in professional tennis. The racket you see in Gauff’s hands on television features the cosmetic livery of the retail Head Boom Pro or Boom MP. However, underneath that paint is a highly specialized frame built to her exact requirements.

Gauff’s frame is a Pro Stock mold designated by Head's internal laboratory with the code PT374.1. This mold features a custom carbon fiber layup (the arrangement and thickness of the carbon layers) designed to provide a specific flex profile. Unlike retail rackets which are manufactured in mass quantities with standard tolerances, Gauff's rackets are weighed, balanced, and customized at the Head Pro Room in Kennelbach, Austria.

This level of customization ensures that every single frame in Gauff's bag behaves identically. A touring professional cannot afford even a 2-gram variance between their rackets, as a slight change in swingweight or balance can lead to errors during critical moments.

2. Technical Specifications: Coco's Setup vs. Retail Boom

To highlight the differences between Coco Gauff’s actual customized racket and what you can purchase in a sports store, let's examine the detailed technical specifications below.

Specification	Coco Gauff's Customized Setup (PT374.1)	Retail Head Boom Pro (Stock)	Retail Head Boom MP (Stock)
Head Size	100 sq. inches (645 sq. cm)	98 sq. inches (630 sq. cm)	100 sq. inches (645 sq. cm)
Unstrung Weight	~310 grams (10.9 oz)	310 grams (10.9 oz)	295 grams (10.4 oz)
Strung Weight	~325 grams (11.5 oz)	~326 grams (11.5 oz)	~311 grams (11.0 oz)
Unstrung Balance	~31.0 cm (Head-Light)	31.0 cm (Head-Light)	31.5 cm (Head-Light)
Strung Balance	~31.8 cm (Head-Light)	~32.0 cm (Head-Light)	~32.5 cm (Head-Light)
Swingweight (Strung)	~322 kg·cm²	~325 kg·cm²	~310 kg·cm²
Stiffness (RA Rating)	~62 (Flexible / Plush)	66 (Stiffer / Crisper)	64 (Moderate Flex)
Beam Width	22mm / 22mm / 22mm (Straight)	22mm / 22mm / 22mm (Straight)	24mm / 24mm / 24mm (Tapered)
String Pattern	16x19 (Open)	16x19 (Open)	16x19 (Open)
Composition	Custom Graphite Layup	Auxetic / Graphene Inside	Auxetic / Graphene Inside
Grip Size	L3 (4 3/8 inches)	Various	Various
Grip Material	Head Leather Base Grip	Hydrosorb Pro Synthetic	Hydrosorb Pro Synthetic

As the specifications show, Gauff's racket utilizes a 100-square-inch head size, matching the head size of the retail Boom MP rather than the smaller, more control-oriented 98-square-inch head size of the Boom Pro. However, her frame is much heavier than the retail MP and features a thinner, more flexible beam width to maximize control and feel on high-velocity swings.

3. The Customization Process: Lead Tape and Silicone Injection

How does the Head Pro Room transform a raw graphite frame into Gauff's customized weapon? The process relies on two primary tuning materials: lead tape and silicone.

Lead Tape Placement

To increase the racket's stability and power, customizers add lead tape to the perimeter of the hoop. When the ball hits the outer edges of the string bed, the racket naturally wants to twist in the player's hand. Placing lead tape at the 3 o'clock and 9 o'clock positions increases the racket's polar moment of inertia, preventing this twisting motion. For Gauff, this added stability is essential when she is blocking back 120 mph serves or sliding into deep defensive positions. It allows her to return the ball deep with a stable string bed even when contact is slightly off-center.

Silicone Injection in the Handle

Adding weight to the hoop increases the racket's swingweight and makes it "head-heavy." To restore a fast, maneuverable feel, the technicians inject liquid silicone into the hollow chambers of the handle. This adds mass directly under Gauff's hand, pulling the balance point back toward the handle (making the racket head-light). According to the United States Racquet Stringers Association (USRSA):

"Tailoring the balance and swingweight of a professional frame is a delicate balancing act. By adding mass to the handle, customizers can increase the overall weight of the frame for plow-through and shock absorption without sacrificing the maneuverability required for modern, rapid-whip groundstrokes."

This combination of a heavy unstrung mass (310g) with a head-light balance (~31.8 cm strung) gives Coco the best of both worlds: high stability to absorb heavy hits, and a fast, whippy feel to generate high racket head speed.

4. Architectural Innovation: Morph Beam and Auxetic 2.0

The Head Boom line stands out in the tennis industry due to its unique geometry. In co-developing this frame, Gauff wanted a racket that felt incredibly solid on defense but did not restrict her ability to accelerate and hit winners.

Morph Beam Geometry

Most tennis rackets use a single, uniform beam shape. The Boom, however, uses a Morph Beam that merges two distinct geometries:

The Square Box-Beam Throat: The throat area features a square, boxy cross-section. Box beams are highly flexible and provide classic, connected feedback. This allows Gauff to feel exactly where the ball is on the strings, boosting her directional control.
The Rounded Hoop: The hoop transitions into a thicker, rounded cross-section. This rounded shape is stiffer and acts like a power frame, returning energy to the ball.

By combining these two shapes, the racket stabilizes her defensive blocks at the throat while offering explosive power and spin potential at the top of the hoop where modern players make contact.

Auxetic Technology

The layup of Gauff’s frame incorporates Head’s Auxetic materials. Placed in the yoke of the racket, Auxetic structures behave differently than standard materials. When stretched, they expand in width; when compressed, they contract.

During a high-impact collision—such as returning a heavy serve—the Auxetic material reacts in real-time, stiffening the frame to prevent twisting and energy loss. On softer touch shots, like drop shots or volleys, the material provides a plush, dampening response. This dynamic feedback is crucial for Gauff’s transition game.

5. String Selection and Tension Management

Even the most advanced graphite frame is useless without the proper string setup. Strings are often referred to as the "engine" of the racket, accounting for up to 50% of its on-court playability.

Head Hawk Touch Polyester

Gauff strings her frame with Head Hawk Touch, a premium co-polyester monofilament. Polyester strings are the gold standard for modern professionals because they are extremely stiff, allowing players to swing at maximum speed without hitting the ball long.

Hawk Touch is engineered with a unique inner core structure that makes it slightly softer than traditional, rigid polyesters. This soft-co-poly composition provides a longer dwell time (the amount of time the ball sits on the strings), giving Coco the control she needs to aim for tight targets. The slick outer coating also enables the strings to slide out of position and snap back rapidly, generating heavy topspin.

Tension and Environmental Shifts

Gauff strings her racket at approximately 55 pounds (25 kg). However, this number is not set in stone. Professional players adjust their tension based on weather, altitude, and ball conditions.

In Cold or Humid Conditions: Air density increases, and balls become heavy. Gauff may lower her tension to 52-53 pounds to get more power.
In Hot or High-Altitude Conditions: The air is thin, and the ball flies faster. Gauff will raise her tension to 57-58 pounds to keep her shots inside the court.

The International Tennis Federation (ITF) rules specify strict regulations regarding racket equipment, but string tension remains entirely at the player's discretion. The ITF's official equipment guidelines emphasize that uniform stringing is essential to maintain a fair, predictable bounce across all professional tournaments.

6. How Coco's Setup Influences Her Playstyle

Every design choice in Gauff's racket is aimed at maximizing her specific strengths while hiding her weaknesses.

Reinforcing the Backhand

Coco's backhand is one of the most stable shots on the tour. The high swingweight and torsional stability of her customized frame allow her to absorb pace and redirect it crosscourt or down the line with deep, flat trajectories. She can step into the court and drive through the ball, knowing the frame will not twist on contact.

Controlling the Forehand

Historically, Gauff's forehand has been her more vulnerable wing, prone to breaking down under extreme pressure or late preparation. Because her forehand swing is long and extreme, she needs a racket that helps her generate topspin to pull the ball down into the court. The open 16x19 string pattern of her 100 sq. inch frame provides a high launch angle, ensuring that even when she hits the ball slightly late, it clears the net with enough spin to land deep.

7. The Retail Alternative: Who Should Play with the Head Boom?

If you are a recreational player, you should not attempt to customize a racket to match Coco Gauff's exact specifications. Hitting with a 325-gram frame with a high swingweight requires perfect timing, clean footwork, and a level of physical conditioning that amateur players do not possess. Doing so can quickly lead to fatigue, late contact, and tendonitis.

Instead, look to the retail versions of the Head Boom:

Head Boom MP: Weighing 295g unstrung, this is the ultimate intermediate frame. It offers the same head size (100 sq. in) and Morph Beam technology as Gauff's racket, but is light enough to swing comfortably for three sets.
Head Boom Pro: At 310g unstrung with a 98 sq. in head, this is designed for advanced players who want the weight of Gauff's frame but prefer a slightly more head-light balance and a tighter sweet spot for maximum precision.

Ultimately, Gauff's setup is a testament to the importance of customization. By tuning the weight, balance, and strings of her Head Boom, she has created a tool that perfectly complements her world-class athleticism.