Welcome to Fully Fit 2026, GOLF’s new platform for providing you with real-golfer insights into what 2026 gear might be best suited for your game. To this end, we assembled six GOLF content creators of varying abilities and ran them through the gauntlet of six full-bag fittings (driver to putter!) at six major club manufacturers in Phoenix and Carlsbad, Calif. Our hope: that you might see shades of your own game in one of our panelists’ and take some learnings and inspiration from their fitting experiences. In this installment (below), Jack Hirsh details the one club he can’t live without from Fully Fit 2026, his Cobra 3DP MB 5-iron. You may browse each of our panelists’ full 2026 dream bags here:
If I was shocked by one thing during my Fully Fit 2026 journey, it’s how easy this muscle back 5-iron could be to hit.
Long irons and I have always had a love-hate relationship.
I’ve hit some incredible shots with them. You know the ones that launch high off the face and rocket into the air directly on line before gently rolling over to the left as they fall back to earth, landing gracefully on the green and releasing toward the pin? Bliss.
But even when I play some of my best golf, long-iron shots can still give me the most trouble. Despite finishing runner-up in my club championship this past summer, the multiple 200-plus-yard par-3s at my club often left me feeling like I couldn’t get a shot airborne. Thank god for match play — but still, I bowed out of the final match after pulling a 5-iron 25 yards left on one of those par-3s.
And that was with an iron set that included a larger and more forgiving 5-iron.
Fast forward to the start of 2026 and now I have a 5-iron — a Cobra 3DP MB — I can stand over and be truly confident that I’ll hit it flush, exactly how I want to. The surprising twist? It looks nothing like the 5-iron I thought would be my solution.
How I ended up in an MB 5-iron
Heading to Cobra’s fitting day for Fully Fit 2026, I had expected to find a set of the new 3DP MB and Tour irons that would be best for my game.
I just didn’t think the long irons would wow me so much.
At first, the new muscle back intimidated me. I’ve never played blades seriously before. Surely I was going to skull or, worse yet, present the hosel, with these compact irons. But I was shocked by how easy they were to hit. That’s owed to the unique 3D-printed construction of the 3DP MB, which you can read more about here.
I compare the feeling to hitting a mini driver off the deck for the first time. It seemed like I was about to drive the ball into the ground, but the soles on modern mini drivers make them almost as easy as a 3-wood to hit from the deck.
Working with Cobra fitter Andrew Lusty, we started with the 7-iron, as most iron fittings do, and it didn’t take us long to see how effortlessly I could hit the new 3DP MB while getting similar numbers to my gamer. We also dialed in a shaft change and a flatter lie angle that has virtually eliminated the left side of the golf course for me.
Still, as small as the 3DP MBs look to me, I couldn’t wrap my head around playing the line’s long irons.
Jack Hirsh/GOLF
That’s when Andrew offered me stock 4- and 5-irons to hit to see if I could hit the intended ball speeds. These were softer and shorter shafts than what I’m spec’d for, but the idea is if you can hit designated ball speeds and peak height windows with stock setups, you should easily be able to with the proper specs.
I was shocked when it took me just one swing to flush the stock MB 5-iron: 141 mph, 110 feet in the air. Exactly the numbers we were looking for.
We broke the set with the 4-iron because I was only able to muster around 141-143 mph out of the MB 4-iron, short of the required 5 mph ball-speed gap. Past the 5-iron was clearly my point of diminishing returns. Switching to the 3DP Tour 4-iron, the feeling of effortlessness returned.
The 3DP MB iron combines the looks and feel of a traditional forged muscle back with the forgiveness of a cavity back iron. The most forgiving blade on the market, the MB has captivated Tour players by checking all the boxes and exceeding expectations with its exceptional stability and feel.
FORGIVING MUSCLE BACK BLADE SHAPE
A slightly revised shape from the KING MB inspired by feedback from PGA Tour player Max Homa, the MB features a thinned topline and enhanced offset. The internal 3D printed lattice and heel, toe and hosel tungsten increases MOI for stability, and positions the CG perfectly centered and lower than the KING MB to promote higher launch.
EXTREME FORGIVENESS MEETS SOFT FEEL
The 3D printed internal lattice structure not only optimizes weight savings, but also provides the stiffness and strength to support the face and fine-tune the acoustics of each iron to produce the most appealing impact sound and feel.
TUNGSTEN WEIGHTING
The discretionary weight savings from the 3D printed lattice allowed for up to 55g of tungsten to be positioned low in the heel, toe and hosel resulting in the perfect blend of a compact blade shape with a low CG and high MOI that mirrors a game improvement iron.
While I had hoped to have played more golf by this point in the year, I’ve hit enough shots to know how much of a game-changer this 5-iron is.
During indoor testing, I hit 8 shots with the 5-iron and recorded a 3.7-yard carry standard deviation with an average carry of 204.5 yards. That basically means my 5-iron is like a pitching wedge, but from 205 yards.
Knowing that is confidence-inspiring, but the ease with which I can still work the ball up, down, left or right has really proved the club’s worth.
My goal with long irons is to make sure I’m just not losing strokes, but with this MB 5-iron, I feel like I finally have a weapon with which I can attack greens from 200 yards.
