Category Archives: String Patterns

Head Prestige Pro 2023 16×19 SMU

I told you something special is coming soon! Soon is here now! And it is special!

Head Prestige Pro 16×19 2023 SMU

We have a limited number of Head Prestige Pro 2023 with a custom 16×19 string pattern instead of the standard 18×20 (we have those as well). These are full custom racquets, meaning they need some customization, and are usually referred to as “Pro Stock” racquets.

These racquets have a different finish than the retail version, primarily shiny instead of a matt finish anywhere.

We receive these in “raw” form, meaning they are not cut or have any post-manufacturing additives, i.e., swing weight and overall weight.

This means we can make a “full custom” version of the retail model up to 27.8 inches long (70.6 mm) except with a more open 16×19 string pattern!

We will add a comparative table for the Pro 16×19 and Retail 18×20.

However, to get things started, we will post the specifications of each racquet “as is.”

Racquet ModelHead Prestige Pro 2023 16x20 SMU
Reference Tension52
MonoGut ZX Pro (PEEK)
Machine UsedTrue Tension Professional
String Bed Stiffness - RDC49.0 Units
String Bed Stiffness -FlexFour59.5 pounds
String Bed Stiffness - SBS43.0 pounds
String Bed Stiffness - ERT35
Racquet Flex, RDC57 - After stringing
Racquet Flex, FlexFour43.0
Racquet - In Plane Stiffness346.1 lbs/Inch
Weight, Grams296
Weight, Ounces10.44
Balance, mm331
Balance, Inch13.03
Length, Cm68.6
Length, Inch27.03
Head Width9.476
Head Length13.052
Head Area, cm2626.7
Head Area, Sq. Inch97.1
Beam Height @ Grip, mm20.0
Beam Height @ Mid, mm20.0
Beam Height @ Tip20.0
Beam Width @ Grip, mm10.7
Beam Width @ Throat, mm10.8
Beam Width @ Mid, mm11.5
Beam Width @ Tip, mm12.2
Number of Main Strings16
Number of Cross Strings19
Ratio Cross/Mains.611
Main String Grid7.25
Cross String Grid10.0
Density (% of head filled with string)74.6%
Average Cross String Space.526
Average Main String Space,453
Dynamic Tension, Kp, ERT35
Dynamic Tension, Lbs/in195.76
First Moment, Nm.758
Polar Moment299.0
Torsional Stability14
Swing Weight, Kg/cm2285.0
Swing Weight, Ounces10.05
Swing Weight Calculated324.3
Power, RDC37
Control, RDC64
Manueverability, RDC97
Power, Calculated 1593.8
Head Points3.78
Head Weight, %48,3%
Center of Percussion20.3
Dwell Time, ms6.048
Efective Stiffness - lbs26.3
K, Lb/In157.05
Recoil Weight129.23
Twist Weight199.70
End Weight 117.0
Tip Weight 179.2
9 O'Clock89.5
3 O'Clock90.0
Butt Cap116.6
COF, Main.412
COF, Cross.331

Wilson SHIFT 99 PRO – Jason’s Racquet Review


Fun racquet to try! Very different in both looks and feel, from the usual Wilson offerings. More suited to the advanced player, and aggressive baseliners who play with fast swing speeds, and a lot of spin.


The most noticeable impression, on first pick up, of the PRO version, was the slightly thicker beam, and overall heft of the racquet. At 327g swing weight, this racquet is definitely in the heavyweight category, but it had a good feel in the hand, and generally good maneuverability, both at the baseline and at the net. As for looks, the contemporary aesthetics are very different from the usual Wilson look, and the string bed looks noticeably tighter than I’m used to.


The sweet spot on this racquet feels small, suiting it to a more advanced player. Faster swing speeds seemed to produce more control, but with the smaller sweet spot, and low dwell time, I experienced some balls flying when I didn’t expect them to. The tight string bed does produce a lower trajectory, but I didn’t find that this prevented those occasional wayward balls. At the net, the racquet had a damper feel than I’m used to, and again, I felt I was in control as long as I hit the sweet spot.


I was looking forward to testing this racquet because of the new increased horizontal bending in the head of the racquet, which should generate more spin. Hitting my regular strokes, I didn’t notice any extra spin being produced naturally. However, when I really tried to increase the swing speed, and increase the spin myself, the racquet responded well and would allow for great spin creation.


The thick beam gave the racquet a very solid and stable feel, and with the weight of the racquet, it was very powerful coming off the sweet spot. Great on days you’re playing well, but if you miss the sweet spot the racquet had a dull, non-responsive feel. Solid on returns and good momentum, but the flatter hitter may struggle for control.


This is a very different racquet that takes a while to get used to. It would be well suited to an advanced player, who swings fast, and already plays with a lot of spin. Don’t expect this racquet to transform flat strokes into heavy topspin. I tested at 55 lbs but would string a little tighter than this if using it again.

Now you have Jason’s perspective! Click here to look at the “numerical” review of this racquet and see how the two reviews stack up!

I did also test the non-pro version of the Shift. With the more open string bed and lighter weight, I experienced even more balls flying long than with the pro version. It was definitely more forgiving on the arm, and easier to maneuver, but the trade-off was less control. Would be well suited to a more intermediate player. I feel an advanced player would have to add some extra weight, and string tighter.

Click here to see Jason’s tennis biography. Please contact Jason if you have questions or anything to contribute to the review!

Compare Wilson Shift 99/300 to Shift 99/315

Comparisons are fun and can be informative as one of the steps in selecting a tennis racquet that is right for you!

If you have read the individual reviews of these two (2) racquets you may wonder about some of the numbers.

This comparison table makes it easy to see the properties.

  • You will notice very little difference in these racquets’ overall weight and swing weight. Typically tolerances will be in the plus/minus 7-gram range.
    What does that mean?
    For example:
    • A 300-gram racquet can weigh from 293 to 307 grams.
    • A 315-gram racquet can weigh from 308 to 322 grams.
      • Different model racquets can be the same weight. 
      • Same-model racquets can be an ounce different in weight.

This much variation is very rare!

So, when multiple racquets are received at the World Headquarters they are characterized to match similar racquets within a model.

Wilson Shift 99/315 Pro

The Wilson Shift has introduced a new movement in racquet design, and the Shift 99/315 Pro rounds out the two (2) racquet series for now!

If you read the review of the 99/300 Shift, you have a good idea about the concept: on the impact, the ball moves the head down, and before the ball can leave the strings, the head moves up! 

It is like you are swinging from low to high! It sounds simple, but there is more to it than that.

Look at the numbers below then we will have a comparison of the two (2) versions! Click here to get a refresher course on what the numbers mean


Racquet ModelWilson Shift 99/315 Pro
Reference Tension50
Babolat Xalt 130
Machine UsedBabolat Racquet Station
String Bed Stiffness - RDC60.0
String Bed Stiffness -FlexFour64.6
String Bed Stiffness - SBS45.0
String Bed Stiffness - ERT38 kg/cm
Racquet Flex, RDC70 After Stringing
Racquet Flex, FlexFour45.0
Racquet - In Plane Stiffness383.6 Lbs/In
Weight, Grams338
Weight, Ounces11.92
Balance, mm321
Balance, Inch12.64
Length, Cm68.6
Length, Inch27.03
Head Width9.79
Head Length12.74
Head Area, cm2632.1
Head Area, Sq. Inch98.0
Beam Height @ Grip, mm23.0
Beam Height @ Mid, mm24.0
Beam Height @ Tip24.0
Beam Width @ Grip, mm12.75
Beam Width @ Throat, mm12.8
Beam Width @ Mid, mm11.1
Beam Width @ Tip, mm13.0(including bumper)
Number of Main Strings18
Number of Cross Strings20
Ratio Cross/Mains.692
Main String Grid7.13
Cross String Grid10.44
Density (% of head filled with string)76.0 %
Average Cross String Space.522
Average Main String Space.396
Dynamic Tension, Kp, ERT MasterTensometer38 kg/cm
Dynamic Tension, Lbs/in212.54
First Moment, Nm.832
Polar Moment341.0
Torsional Stability17
Swing Weight, Kg/cm2324
Swing Weight, Ounces11.43
Swing Weight Calculated346.3 (full-length)
Power, RDC49.0
Control, RDC51.0
Manueverability, RDC74.0
Power, Calculated 2244.1
Head Points6.93
Head Weight, %46.8%
Center of Percussion21.0
Dwell Time, ms5.94
Dwell Time, Spin, ms8.21
Efective Stiffness - lbs32.3
K, Lb/In192.31
Recoil Weight161.30
Twist Weight242.30
End Weight 135.9
Tip Weight 193.8
9 O'Clock98.2
3 O'Clock99.0
Butt Cap130.4
COF, Main.396
COF, Cross.319


A Players Perspective

We are really happy to have Jason Harne join us to review and add his comments on tennis racquets and tennis strings!

I think you will agree that Jason will be a great addition to based on the following tennis bio:

Jason Harne – Tennis

  • Pro tennis – futures tournaments and satellites
  • Stirling University, Scotland. One of the first players to be awarded the British Universities Tennis Bursary Colors Award (equivalent to All-American)
  • International home nations tournament, representing Scotland, player of the tournament award.
  • England county cup, division one, representing Yorkshire County.
  • Spain and UK, national league tennis
  • High Point University, Big South Conference, 22-2 record.
  • U21 guardian direct British futures, national champion, and fastest UK serve.
  • Teaching pro, UK and Spain, high-performance players

This is very impressive but the most important component for us, and you, is Jason’s incredible interest in new things!  Jason is willing to try, and honestly comment on, any performance tennis equipment.

Jason will be commenting on the new Wilson Shift series later this week.

Please leave a comment or question for Jason.