Callaway's Great Big Bertha products (that came back into the limelight in 2014) continue to evolve. I've compared drivers to mobile phones in the past -- if you're playing with one that's more than a couple of generations old you're probably missing some big breakthroughs, not just a few small features.

In this case, that "leapfrog" feature is Jail Break - something so revolutionary it's even got the engineers at Callaway using new terms like "energy lensing." Simply put, Jailbreak technology makes the face of the club more efficient by providing more focused energy back to the ball as it releases from the face. (Get it? That's the lensing part.)

Jailbreak consists of two vertical bars connecting from the sole to the crown behind the clubface, invisible to the golfer other than when the club is turned over. (There's also a not-so-subtle hint in the two silver disks on the cool green, black, and white headcover.) What I like about the technology is it just works, for everyone. No adjustment needed. Golfers tested by Callaway saw increased ball speeds, resulting in more distance off the tee.

I noticed a really solid feel, sound, and more distance than the Great Big Bertha right from the get-go. The 55 gram Project-X HZRDUS shaft that comes standard is a nice mid-spinning lightweight, but very stable addition and a really nice piece of standard equipment. But there are plenty of shaft options available, as Callaway continues to see more people use the fitting services of their golf shop or pro.

“Jailbreak Technology creates a new and remarkably efficient working relationship between the face, crown and sole to promote faster ball speed across more of the face to give the golfer more distance,” said Dr. Alan Hocknell, Callaway’s senior vice president of R&D.

HEAD SHAPE AND DESIGN

The black crown with green accents and a nice alignment system sits beautifully at address. The shape is confidence-inspiring. Beyond the graphics, and the fact that the Triaxial Carbon is visible on the back of the crown, there is a functional element called "Speed Step" built in, which helps reduce drag. Every mile an hour gained is worth chasing, and Callaway has spent a great deal of time working with big aerospace partners to come up with the right formula.

MATERIALS

The engineers at Callaway look at "discretionary weight" as an opportunity to get creative. Jailbreak is one example of that. Even at only 3 grams per vertical Jailbreak bar, the weight has to be saved someplace else. Two unique technologies are blended in GBB Epic to free up that weight. One is the use of Triaxial Carbon in the crown. It's twice as strong as the material they've used in previous models. It merges perfectly with the Titanium Exo-Cage, which holds the Triaxial Carbon in place. First implemented in the GBB Fusion driver released earlier this year, this stiff material also holds a large amount of weight in the back of the clubhead that helps create a low and deep CG and a high Moment of Inertia. That means forgiveness, consistent launch conditions, and an immediately noticeable sound and feel.

If you're interested in learning more, I suggest you watch the video below:

FITTING SYSTEM

Another benefit Callaway has put into the design, as a result of the aforementioned discretionary weight, is more ball flight adjustability for Epic via its Adjustable Perimeter Weighting technology, which allows for final tuning of ball flight based on your individual swing. And compared to previous Callaway drivers, Epic’s rear "track" has been redesigned and the sliding weight has been increased to 17 grams. This delivers a full 21 yards of potential shot-shape correction (a 22 percent increase compared to the previous Great Big Bertha) to dial in straighter, more accurate flight while maintaining high MOI (or Moment of Inertia). Good stuff!

SHAFT OPTIONS

Four premium, Tour-proven stock-shafts are available, distinguished by weight class and each engineered to promote a formidable combination of speed, power, stability, feel and control: Project X HZRDS Green, MRC Diamana Greenboard, Fujikura Pro Green and Aldila Rogue Max. A long list of custom after-market shafts is also available.

PRICE AND AVAILABILITY

GBB Epic driver availability begins at retailers nationwide and on CallawayGolf.com January 27, 2017 at the new product introduction price of $499.