Bolstering Callaway’s Super Game Improvement iron category comes the Big Bertha OS iron, the company’s most complex iron ever made promoting distance without losing out on forgiveness.

It does this through an Exo Cage construction, similar to the concept found in the Callaway Big Bertha Fusion driver, which combines strength and light weight to distribute more discretionary weight into more optimum locations. This makes the iron more stable on off-centre hits, allowing Callaway’s next-generation 360 Face Cup technology to function more efficiently for more ball speed across the face.

The Exo Cage provides vertical stiffness with minimum weight in the iron through two beams behind the face, meaning the back of the iron behaves in a rigid manner for more ball speed. The transition area between the face and hosel that is normally solid has also been made hollow, saving even more weight to make the club more user friendly.

Through the set, 100g of tungsten has been used in various ways, controlling the centre of gravity (CG) in both directions. The CG is low in the head in the long irons to increase launch angle, and higher in the short irons to reduce trajectory and increase spin for added control.

There is also a lighter club weight and higher lofted set configuration for seniors and women to promote faster ball speed and higher launch angle to make it easy to get the ball in the air for slower swing speeds.

Big Bertha OS Hybrids

Joining the Big Bertha OS irons is the Big Bertha OS Hybrid, which delivers more launch and distance thanks to its deeper body, larger and faster face, and next-generation Face Cup technology.

A larger and more flexible face not only gives you more area to make contact with, but the added flexibility pushes the COR closer to the USGA limit, promoting faster ball speed for more distance.

Designed with the assistance of aerodynamic experts, Callaway’s Speed Step Technology improves airflow to promote faster clubhead speed for more distance. A Dual Runner Sole design promotes better turf interaction for more consistently solid contact.

Callaway’s adjustable Optifit Hosel lets you choose from eight loft and lie settings to dial in the launch angle and shot shape that promote maximum distance and accuracy with your swing.

Tech specs, prices and availability

The Callaway Big Bertha OS irons come with True Temper Speed Step 80 steel shaft (RRP £849, 7-piece set) or the UST Recoil ES 460 graphite shaft (RRP £1099) and will be on sale from Sept 30^th. The Big Bertha OS Hybrids have an RRP of £229 per club with a UST Recoil ES 460 shaft as standard in lofts 3H (19°), 4H (22°), 5H (25°), 6H (28°), 7H (31°).