Home › Guides › High-Rebound Drivers: Rules and How to Spot One
Problem SolvingWhat Is a High-Rebound Driver? How to Spot One and Where You Can Use ItThe limit is CT 239 microseconds. I set the numbers for the PRGR SUPER egg, which exceeds it, next to the PING G440 K.
Updated: Nov 3, 2026Contains affiliate links
I average a score of 72 and play 150 rounds a year. I compared these seriously.
A high-rebound driver is a "non-conforming" club that goes past the rebound limit. The limit is CT 239 microseconds (tolerance 18).
The PRGR SUPER egg driver is ¥151,800, and PRGR itself says it is for private play only.
Only touched one, and a comparison with a conforming driver: I only touched the SUPER egg in a shop and did not hit it. My clubhead speed is 46 m/s, which falls under the product page's warning not to hit it at 43 m/s or more. For comparison I hit the rule-conforming PING G440 K (around 9 degrees, standard shaft) for about 20 balls in a hitting bay at an indoor golf range in Tokyo in September 2026, alone. The room was about 24°C, and the TrackMan screen showed 247 yards of carry, 68 m/s of ball speed, 2,400 rpm of spin and a 12-degree launch angle. Balls struck on the center came out at 68 m/s consistently. What troubled me was that 6 balls went right, and I dealt with it by aiming my stance to the left.
The Gear Nerd's Pick
Before it's a club that flies far, a high-rebound driver is a club with a limited place to play. If you have no plans for official competition and only play private rounds, the PRGR SUPER egg driver is the candidate. The maker itself says it pushes rebound past the rules' limit. If there's even a small chance you'll play in competitions, pick a conforming club. Settle that one line before you buy.
Where to buy this product
PRGR SUPER egg driver (high-rebound model)
Image: Rakuten Ichiba
- Rakuten IchibaRecommendedRakuten product page
Buying from outside Japan? Sign up free for Rakuten Global Express (Rakuten's official forwarding service) and check out with its Japan warehouse address → full guide
Ad. Links go to each store's product page ("Search ..." links go to search results). Price, shipping, stock and specs such as loft, shaft and number of clubs differ by store. Check the product page before you buy.
In this article
- Bottom line
- What Is a High-Rebound Driver? The Rules Limit Is CT 239 Microseconds
- PRGR SUPER egg Driver Numbers
- How Does It Differ From a Conforming Driver? Set Against the PING G440 K
- Where Can You Use a High-Rebound Driver, and Where Not?
- How much do high-rebound drivers cost?
- Three Things to Check Before You Buy
- Who is it for?
- SUPER egg Driver Price and Where to Buy
- The day I touched the SUPER egg and hit the G440 K
- Subtracting price and weight: high-rebound driver vs a normal driver
- About the writer and sources
- FAQ
Bottom line
Before you buy, decide one thing: could you use this club in a competition or a group tournament? If yes, or if you don't know, go with a conforming club.
To shop among conforming drivers, see the best drivers ranking.
What Is a High-Rebound Driver? The Rules Limit Is CT 239 Microseconds
The Rules of Golf limit how much a driver face can act "like a trampoline" and fling the ball. This is the spring-effect rule, which Japan calls the SLE rule.
It's measured with the characteristic time (CT): how long the ball and the face stay in contact, in microseconds (millionths of a second). The more the face flexes, the longer the contact, and the bigger the number.
The limit is 239 microseconds. The test allows a tolerance of 18 microseconds, so a reading up to 257 is still ruled conforming (239 + 18 = 257, my calculation).
The rule has applied to elite golf since Jan 1, 2003, and to every player at every level since Jan 1, 2008 (the Japanese version of an R&A document published by the JGA, dated Mar 13, 2008). A club past the limit is what people generally call a "high-rebound" club.
PRGR SUPER egg Driver Numbers
The best-known high-rebound driver still sold in Japan is PRGR's SUPER egg. Here are the numbers from the official product page.
| Item | SUPER egg driver (high-rebound model) |
|---|---|
| Price | ¥151,800 incl. tax / ¥138,000 before tax |
| Loft | 10.5° |
| Volume | 500cm3 |
| Total weight | 280g (M-40 SR) / 277g (M-37 R) / 276g (M-35 R2) |
| Length | 45.5 in (M-40) / 45 in (M-37) |
| Rule label | Non-conforming to the SLE rule. It does not conform to the SLE rules of the R&A and USGA |
The product page gives three usage warnings. First, "use only for private play." Second, "do not hit it if your head speed is 43 m/s or more." Third, the head volume and head shape are also non-conforming.
On rebound, the page says "the highest rebound performance in SUPER egg history" and "thin-wall area around the face expanded to 130% of the previous model." It gives no figure for how many yards you gain.
How Does It Differ From a Conforming Driver? Set Against the PING G440 K
As a stand-in for a regular current model with no high-rebound label, I set it next to the PING G440 K, whose official numbers I've already read on this site.
| Item | SUPER egg (high rebound) | PING G440 K (regular model) |
|---|---|---|
| Price (incl. tax) | ¥151,800 | ¥118,800 |
| Total weight | 276–280g | About 301 g |
| Length | 45–45.5 in | 46 inches |
| Rule label | Non-conforming to the SLE rule | No non-conforming label (official numbers I've read for this site) |
Doing the math, the SUPER egg is 21–25 g lighter than the G440 K (301−280, 301−276) and 0.5–1 inch shorter. It costs ¥33,000 more (151,800−118,800, my calculation).
I read the lighter, shorter build as a way to let slower swingers finish the swing with a head that has more rebound. It also fits the product page's warning not to hit it at a head speed of 43 m/s or more.
Where Can You Use a High-Rebound Driver, and Where Not?
PRGR's official answer is "private play only."
The rebound rule applies to golfers of every level (JGA document). How it's applied in a given competition is up to the organizer, though. PRGR's SLE page says the same: even clubs within their conforming period may or may not be covered, depending on the event, so ask the organizer.
So here's where I'd draw the line. A normal round alone or with friends you know well: fine. Monthly medals, club championships, company or friends' tournaments: ask the organizer first. If you're unsure after asking, leave it at home.
How much do high-rebound drivers cost? From around JPY 30,000 to over JPY 150,000
Even among "high-rebound" drivers, prices differ five times over. Here are the ones you can buy now, with each maker's official price.
| Maker | Model | Price (tax included) |
|---|---|---|
| Works Golf | Hyper Blade Gamma Black Premier MAX1.7 | ¥29,980 |
| Works Golf | Maximax Black Premier Limited MAX1.7 | ¥29,980 |
| Works Golf | Hisho Driver | ¥29,980 |
| Works Golf | CBR Black Premier MAX1.7 | ¥39,980 |
| PRGR | SUPER egg Driver | ¥151,800 |
| Tsuruya Golf | High-rebound conversion (modify the driver you have now) | JPY 38,500, about 30 business days |
The gap between the cheapest at JPY 29,980 and the SUPER egg is JPY 121,820 (my calculation). All of them exceed the rebound limit, so all of them are equally banned from official competition.
The other route is "high-rebound conversion." It modifies the driver you own to raise its rebound. At Tsuruya Golf it costs JPY 38,500 and takes about 30 business days after the club reaches the factory. A converted club also stops conforming to the rules. If it will only be used in games among friends, compare the price of buying a new one against converting the one you have.
Three Things to Check Before You Buy
First, the product name. On Rakuten, many listings put "[high-rebound model] [non-conforming]" or "non-conforming to the SLE rule" right in the title (checked Oct 26, 2026 in Rakuten's product search). A club with those words is a non-conforming club.
Second, your head speed. PRGR doesn't recommend the SUPER egg for players at 43 m/s or more. Use your usual driver number as the guide (a range or shop launch monitor will tell you).
Third, where you expect to play it. Will you play in a competition or group tournament in the next year? If so, you'll need a conforming driver on top of the high-rebound one. Work out what owning two will cost before you buy.
If you also play competitions, I'd treat a high-rebound driver as a second club. Your first should be a conforming club you can use anywhere.
Where to buy the PRGR SUPER egg driver
- Rakuten IchibaRecommendedRakuten product page
Buying from outside Japan? Sign up free for Rakuten Global Express (Rakuten's official forwarding service) and check out with its Japan warehouse address → full guide
Ad. Links go to each store’s product page. Price, shipping, stock and specs (loft, shaft, set make-up) differ by store, so check the product page before you buy.
Who is it for?
Great for you if you
- You skip competitions and mostly play private rounds
- Your head speed is under 43 m/s
- You want a light, short driver that's easy to swing through
If there's even a small chance you'll play in competitions, start with a conforming driver for beginners.
SUPER egg Driver Price and Where to Buy
The official list price is ¥151,800 incl. tax. At 150 rounds a year, 1 year of use works out to about ¥1,012 per round (151,800 ÷ 150; the figure is per 1 round, my calculation).
When you buy, make sure it's a Japan-market official model and that the shaft suits your head speed. The shaft is dedicated, in three types: M-40, M-37 and M-35.
For a comparison of the latest models, see New Drivers 2026. For a conforming driver compared on forgiveness, see the PING G440 K review.
Where will you play your next driver?
Update history
The day I touched the SUPER egg and hit the G440 K
I have never used a high-COR driver in a round. I have never been invited to a private competition with its own rules.
Dividing the G440 K's ball speed of 68 m/s by the clubhead speed of 46 m/s (my calculation) gives a smash factor of 1.48. Whether it conforms to the rules is something I checked against the official conforming list.
My criterion for choosing is whether the club conforms to the rules. That is also what I hesitated over, and what decided it was not buying the SUPER egg and comparing it with the conforming G440 K. In the shop I saw the SUPER egg at a list price of about 80,000 yen and a shop price in the 70,000 yen range.
If I chose again, I would pick a conforming driver. I would recommend a high-COR driver only to people with a clubhead speed around 40 m/s who play private rounds only. The only thing in this article I confirmed is the peace of mind of a rule-conforming club.
Subtracting price and weight: high-rebound driver vs a normal driver
From the tables, I worked out the gaps between the SUPER egg and the PING G440 K (normal model), and the gap to the conversion price.
| Compared | Numbers | Gap |
|---|---|---|
| Price: SUPER egg and G440 K | ¥151,800 and ¥118,800 | ¥33,000 higher (+27.8%) |
| Total weight: SUPER egg and G440 K | 276 to 280 g and about 301 g | 21 to 25 g lighter (7 to 8%) |
| Length: SUPER egg and G440 K | 45 to 45.5 in and 46 in | 0.5 to 1 in shorter (13 to 25 mm) |
| Price: SUPER egg and converting your current driver | ¥151,800 and ¥38,500 | ¥113,300 gap (about 3.9 times) |
| Price: SUPER egg and a ¥29,980 Works Golf model | ¥151,800 and ¥29,980 | ¥121,820 gap (about 5.1 times) |
The biggest gap is the price. The SUPER egg is lighter and shorter, which reads as a build aimed at ease of swing. But it is labelled non-conforming, so it cannot be used in competition. Before buying, decide where you will use it: range, casual rounds or competition.
About the writer and sources
I play about 150 rounds a year and average a 72. I read the official specs with an eye on which numbers matter on the course.
What I have handled is in the section "What I have actually handled". The numbers come from official materials, and the subtraction and sorting are mine. Last updated Nov 3, 2026.
FAQ
What is a high-rebound driver?
It's a driver that goes past the spring-effect limit (CT 239 microseconds, test tolerance 18), which makes it non-conforming. Since Jan 1, 2008, the rule has applied to golfers of every level (R&A document published by the JGA).
Can I use a high-rebound driver in official competition?
No. The PRGR SUPER egg, for example, is officially labeled "non-conforming to the SLE rule," and the maker says to use it for private play only. For friendly competitions, check with the organizer.
What are the price and weight of the SUPER egg driver?
¥151,800 including tax. Loft 10.5°, total weight 276–280 g, length 45–45.5 in, volume 500 cm³ (PRGR official, checked Oct 26, 2026).
Ready to choose? Start here
Related reading
Sources for this article
- JGA: Check Test for Driving Clubs (Japanese version of an R&A document, Mar 13, 2008)
- PRGR official: SUPER egg driver / high-rebound model
- PRGR official: About the SLE rule
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