At the 2013 Masters, Phil Mickelson brought a secret weapon, a club that was inspired by him as Callaway built him the “Phrankenwood!” This club was a modern 2-wood that Phil could hit as long as his driver but with a flatter ball flight and more shot-shaping control. Callaway has brought this technology to the public with the X-Hot series and continued it this season with the X2 Hot!
As previously suggested, the “Deep Series” fairway wood was inspired by Tour professionals who want a second driving club. Dr. Alan Hocknell, Senior VP of Callaway R&D, explains that the X2 Hot Deep fairway woods series takes advantage of the hot fairway wood faces.
With the 3 Deep, the club provides a driver like launch condition with a higher launch and less spin. The 2 Deep, also thinking along the lines of a second tee club, provides a stronger ball flight but the 5 deep is designed for players who want to hit more towering trajectories with a higher launch, lower spin and steeper landing ball flight characteristics.
Source: Callaway Golf YouTube