Cobra make a pretty decent mid-sized iron and the King F7 follows on from the previous King F6 iron with a shape and set make up that is pretty similar.

This is classic Cobra style with an easy on the eye, mid-sized top line combined with a reasonable offset to give a solid look at address.

In the King F6 the back of the 4-iron started to peer out at address, but in the King F7 it seems a little more hidden, which is a good step forward.
The Speed Channel that was around the edge of the cavity and the sole before has been replaced by a new PWRShell face that aims to do the same job, but better.

The PWRShell face and the sole are thinner than before and by increasing the ball speed across the face, Cobra claim that the 'Sweet Zone' is even bigger, thus making the King F7 irons more forgiving because the drop off in ball speed will be less and certainly the margin for error is pretty good.

The new cleaner Nickel Chrome look of the King F7 is a good change and features a subtle black and orange graphic on the Thin Optimized & Personalized (TOP) medallion, which has to be a challenger for Made Up TLA Of The Year.

What the TOP medallion does is dampen vibrations for feel and save a weight that is then placed lower in the head to drop the CG a little further. It varies in size and shape as you go through the set to enable it to be 'personalized' to the club style as it changes.
The King F7 set follows the same collection of four heads styles as the F6, which Cobra says is to maximise the performance of each individual iron.

In the 3 to 5-iron it features a Full Hollow design that has the furthest back and lowest CG of the set. You need this in the long irons for forgiveness and to get the launch high enough to enable the ball to land and stop before it runs off the green.

This does give it a bit of a hollow sound at impact, but results-wise it does the job with ease.
The 6 and 7-irons feature a Half Hollow design that sees the only the bottom half of the hollow head remain with the cavity covered up.

It goes very well too and as you would expect the sound is a little more solid than the full hollow. The performance is good and it feels the best of the four styles as it has a more lively feel at impact.
The 8-iron to PW features a traditional open Cavity back design that plays well for such a lofted club and keeps the flight on a good trajectory.

Finally the GW and SW have a Speciality wedge design that still features a small cavity, but this time it is closed up in the sole of the club so you can't see it.

It looks like a blade, and with the slightly thinner sound it also sounds like one, but it actually plays a little more forgiving than this. WhiIst it was good, I would probably prefer the wedges from the King Forged Tour set, so it may be worth seeing if you can blend these in if the King F7 version is not to your taste.
However keep an eye on the distance gaps as the standard King F7 shafts are progressively longer than those on the King Forged Tour, rising up to 0.75 inches longer on the 4-iron.
Cobra is not alone in trying the 'optimised head design for each club' approach, but I am yet to be fully convinced that this gives the optimum overall set. It's great if you a mixing and matching fanatic, but if you like your irons sounding and feeling the same from top to bottom then this approach may not be for you.

To be fair the Cobra King F7 irons do feel pretty good throughout the bag in their own way, so try them and see how they appeal to your eyes, ears and fingers.
The King F7 irons come as standard with steel or graphite shafts that are longer in the long irons and shorter in the short irons. This may sound like I am stating the obvious, but now you have a choice, because you can also have them in a single shaft length as the Cobra King One Length irons review reveals.

The One Length is a really good option and the variable head design of the King F7 really comes into its own here, especially in the long irons where the deeper CG of the Full Hollow design really helps with the launch.

Shaft length apart the King F7 irons are more evolution than revolution in terms of construction. Sometimes that is a good thing and the King F7 continues the easy playing, forgiving, competitively priced mid-sized irons that Cobra do well, but in a better looking package than before.