reString Mailbag October 2026

We're back for another mailbag, where we answer questions from real customers.

This month, we will cover a hybrid in the HEAD Gravity Pro, a Luxilon ALU Power replacement plus how often to restring it, reString Sync in the mains with reString Zero in the crosses, and the full bed tension range for reString Sync.

Question 1 - HEAD Gravity Pro Hybrid

Hi, I have a HEAD Gravity Pro 2025 model, 18x20, and I currently have a full bed of HEAD Ultra Tour 16G poly in it, which I like.

But my elbow is getting stiff after hitting, so I want to try a hybrid before I start feeling elbow pain. I'm thinking of HEAD Velocity 17G and reString Sync in 17G.

I tend to hit a flatter ball with good power, but I'm working on hitting a deeper one with more spin so it comes up higher and gives me a bit more margin.

Should I put reString Sync in the mains and the Velocity on the crosses? How would this combo compare to a full bed of Velocity MLT, which I have used before I tried polys?

reString Response

For arm comfort, the standard approach is to put the softer string in the mains, since the mains take on most of the impact and vibration.

So we would recommend HEAD Velocity MLT in the mains and reString Sync in the crosses rather than the other way around.

This "reverse hybrid" setup is the go-to for players moving off a full poly bed who want to ease up on the elbow while still keeping some bite from the poly crosses.

Compared to a full bed of Velocity MLT, this hybrid should feel noticeably more comfortable than your current full poly setup, while still giving you extra spin, control, and durability from the reString Sync crosses that a full multifilament bed alone would not provide.

You will likely notice a bit less overall softness than a full Velocity MLT bed, but you should get more margin and bite on your shots, which sounds like exactly what you are working toward.

One more tip: we would recommend stringing about 2 lbs below your usual poly tension. That tends to bring out the best snapback and comfort with our strings.

Question 2 - Luxilon ALU Power Replacement

Hello, I'm trying to find a replacement for my Luxilon ALU Power string, as I've learned it goes dead quickly.

I play with a Wilson Shift 99L (16x20) and have been stringing it at 50 lbs with ALU Power 17G (1.25mm).

I've read mixed recommendations if I use reString Sync, to go down to 1.20mm at 48 lbs or 1.25mm at 48 lbs. Do you have a recommendation?

reString Response

reString Sync is a great pick coming from Luxilon ALU Power. It's a round poly with a soft, controlled feel and excellent tension maintenance.

It's also built with our Signature Snapback technology. Instead of just an outer coating, the lubrication is infused throughout the entire string.

That helps it resist notching (the grooves that form where the mains and crosses meet), which is the main reason a stringbed starts to feel dead. So you get that fresh snapback feel for a lot longer.

Our recommendation would be reString Sync 17G (1.25mm) at 48 lbs.

It's the closest swap to your current ALU Power 1.25mm setup, and we suggest stringing about 2 lbs lower than your usual poly tension so you get the most out of the snapback.

If you'd like a little more feel and bite on the ball, the 18G (1.20mm) at 48 lbs is a great option too, especially on a 16x20 pattern like the Shift 99L. Just keep in mind the thinner gauge trades a bit of durability.

Question 3 - Zero and Sync Hybrid

Hello, I hybrid gut mains with reString Sync crosses. I'd like to try reString Sync in mains and reString Zero in crosses. However, I see that folks normally use reString Zero in mains.

I am arm-sensitive. What do you think of my idea?

reString Response

We usually recommend reString Zero in the mains with reString Sync in the crosses.

The mains dictate play the most, so reString Zero up top gives you maximum spin and bite, while reString Sync in the crosses smooths things out with a softer, more controlled feel.

It really comes down to what you are after. If you want power and spin, reString Zero in the mains is the way to go.

If you want more control and feel, reString Sync in the mains is a great choice, and since you have a sensitive arm, it is a very reasonable setup. reString Zero in the crosses would still add some extra bite.

On tension, we suggest stringing about 2 lbs lower than your usual polyester setup.

For a sensitive arm, we would lean toward the lower end, and a few pounds lower in the crosses can help with comfort too.

Question 4 - Full Bed Tension Range

Hi, I have been using reString Sync as a cross string so far at 25 kg, but I want to start using it in a full bed.

What's the highest tension I can string it at, and the lowest too? I'm using the 1.30 gauge.

reString Response

For reString Sync and most of our strings, we recommend a range of roughly 19-25 kg.

For a full bed, we would suggest dropping your tension 1-2 kg from your starting point today, so somewhere around 23 kg, to allow for our Signature Snapback technology to shine.

Question 5 - Wilson Shift 99L Restring Frequency

I've been playing with Luxilon ALU Power 1.25mm but want something similar that doesn't die as fast. I string at 50 lbs. Should I do your strings at 1.20mm or 1.25mm?

I play with a Wilson Shift 99L, which is 16x20. Please advise!

reString Response

The closest match to your Luxilon ALU Power 1.25mm would be reString Sync.

reString Sync is also a round poly built around control and feel, so it will feel familiar coming from ALU Power, but ours holds tension better and stays playable longer thanks to our Signature Snapback construction.

Since you are used to 1.25mm and want something that lasts, we would recommend sticking with reString Sync 17G (1.25mm) for the closest feel and best durability with your Wilson Shift 99L.

If you want a touch more spin and feel and do not mind restringing a bit more often, reString Sync 18G (1.20mm) is a great option too.

On tension, since our poly resists tension loss well, we would recommend going about 2 lbs below what you are used to, so around 48 lbs.

Followup Question

Thank you! How often do you recommend restringing at both 1.20mm and 1.25mm?

I'm a 4.0 and play doubles. Right now I'm playing mixed 8.0. I play 5-6 times a week, probably 10-12 hours a week.

Followup Response

Our general rule of thumb is to restring as many times a year as you play per week. So at 5-6 times a week, a fresh set every couple of months (around 6 times a year) is a good target for either gauge.

At your volume, reString Sync 17G (1.25mm) will hold up a bit longer between restrings, so that is the one to lean on if you want to stretch the interval out.

If you don't mind swapping in more often for a touch more spin and feel, the 18G (1.20mm) works great too.

Got Your Own Question?

We'd love to hear from you and share the best response we can to help your game.

If you have your own question, you can submit that via our contact page or on Instagram.

Until next month, enjoy your tennis!

Note: questions and responses have been lightly edited for easier reading.