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C4 Falcon 15 fins

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
I'm amazed that none of you Italian-bound chaps has had a shot of a pair yet.
Well, since no one seemed to know about them, I bought some anyway!

First impression are:

Definitely softer than the 30s and 40s I had.

The footpocket section seems slightly stiffer than my Mtechnics 'hard' (which are 4 years old and may have got softer with time although that seems unlikely???)

To be honest I am suprised. I expected them to be softer.

I will give them some testing this weekend and report back next week.

Ben (and others) what do you think about your 30s and 40s?
I plan to buy some C4 but have not decided yet on witch one 30s 40s 80s.
I was going for the 80s but since, I read quite a few threads about the fact that the ascent should be anaerobic. Which I guess would be helped buy some stiff fins. So I am thinking about the 40s now.
However I am not what you would call a very strong guy, so I am wondering how stiff they are.
Compared to stiff plastic blades for example (I have Omer Tuna at the moment which are fine for my legs)
Other question. I might use them after a while for spearing as well and am a bit worried about breaking them. Do you often touch rocks with them? are they still ok?
i am also trying to decide on which model to get and am waiting for Ben to report how he is finding the C15s. I am currently using the C30s and think these are too hard ... i used to think the harder the better, but doing a course with Umberto last year has changed my thinking significantly ...
I now think that you don't gain much from hard fins unless your technique is perfect ... for most, hard fins just lead to a bicycle style kick - a lot of the course focussed on just getting the finning technique right. I think almost everybody was shocked to see themselves on the video tape ...
At www.c4carbon.com they state:
"The velocity permitted by fins is not directly proportional to their stiffness, it depends instead by the mechanic and hydrodynamic efficiency of the man + fins system."
Umberto's philosophy certainly seems to echo that - i.e. the softer the better - or "as soft as you can get away with" ...
So, after having had fairly hard fins all my life, I am now trying to decide between the C25s vs the C15s !
Regarding the durability - I know quite a few spearos that use C4s for fishing ... you just have to treat them with lots of care e.g when getting dressed on a small cramped dive boat with people stepping over gear etc - they are certainly not as forgiving of rough treatmen as normal plastic fins.msitreatment
I agree that soft fins is to prefer.

To hard fins will only move water:head

It will be interesting to hear what you guys think of the 15's.

The ascent can definately be anaerobic with a softer fin, just choose the fin that makes the propulsion most effective at the speed/distance you want them.
Don't you think you have to fin gently with soft fins to be sure not to over-power them and then loose effitiency? In that case you might have to be aerobic!

Do you think there will be a big difference between 30's and 25's?
I think you should go for the 15's if you already have the 30's
When I first got my 40's I thought that they were the ticket, but that comes after decades of scuba diving in stiff fins. I then went to 30's and found that I liked them much more than the 40's. I would have gone with the 25's right away, but OMER USA doesn't carry them.

At the end of the summer I got a pair of 80's. These are my favorite fins by far. As time goes on I find myself prefering softer fins. The only problem witht he 80's is that they are really too long for the spearfishing that I do around here- they are made for deep stuff.

I would like to try a pair of 15's and see how much softer they really are. I do know that switching between OMER and Sporasub pockets made a big difference with the Special Fins blades that I tried.

I wouldn't be caught dead without my 40's now - seriously the best fin I've used. Haven't had a chance to try any of the other C4's, but this is comparing them to picasso carbonos, omer carbons, omer bats, waterways fibreblades and half a dozen plastic fins. I used to use omer mil comps (one of the original batches that was *realllly* stiff, aparently it was a design flaw or something for this one batch? i've felt others in shops that were no where near as stiff) and they were good, although they did feel like boards. The C4s bend in all the right way, and when I'm depth diving, I dive a lot faster, with less effort, and I barely notice I'm wearing them.
Hi Remi,

this is the decision I'm struggling with! Is there enough of a difference between the 30s and 25s? Until recently I was not aware that the 15s were available, so the decision seemed simple ... now I'm undecided. I'll wait to hear how Ben (or anyone else) finds them in the water.
There are also the M-technic blades to consider which I believe are even softer ...

Caveat: This report is from only 1 session!

I tried them out and compared them to my Mtechnic 'hards', and deduced the following:

They are similar in stiffness to my Mtechnic hards, and I would say they are a tiny bit stiffer.
The fin tips are softer on the Mtechnics.
The foot section is similar on both.
The C4s flex more evenly on land, but underwater they are similar.
The ribs are bigger and clumsier and probably 'sap' some energy on the C4s.
The Mtechnics feel as though they have more 'snap'.

Overall: I prefer my Mtechnics as they seem to have a higher quality of snap.


I bought these for casual freediving and spearfishing in my 7:5mm neoprene suits. Not for deep performance diving. The bulkier fin ribs, whilst they may reduce performance, certainly protect the fin much better than the ones on the Mtechnics.

I dive on FRV/FRC/exhale almost exclusively, and so I don't 'need' as stiffer fins as most others. In a 7:5 suit with full lungs and diving to 25m+, I would probably want a stiffer pair (30s/40s).

One would imagine that a 30 is twice as stiff as a 15 - I doubt this. I imagine the 15:25:30:40 has some sort of relevance to their construction, but it is probably best to think of them as medium:medium-hard:hard:extra-hard in stiffness.....
Don't you think you have to fin gently with soft fins to be sure not to over-power them and then loose effitiency? In that case you might have to be aerobic!

Yes, if a fin is too soft. I have not tried the 15's so I dont know if this is the case with them. Most fins are to stiff in my opinion but during my first 2-3 years of freediving, my opinion was the opposite because of bad technique.

If you have a good technique it's much easier to know if a fin is good or bad, you can immidiately feel if a fin "stalls" or if it's to weak for any given speed.
Ok, I think I am back on the 80's after reading all your posts.
I'll continue to think about it, but might be going for the soft ones

There are many things that affects what stiffness a diver should choose:

1. Bodyweight
2. Bodylength
3. Bodystrength
4. Technique
5. Speed at which you want to go
6. Discipline at which you want to use them.
7. Diving strategy

That makes the choice hard and a choice that is obvious for one diver can be wrong for another.

Good luck and try as many fins you can before you make up your mind!!
Hi everyone
I am thinking of new fins.
Been using Sporasub H Dess for a year.

1 - about 13 stone / 85kg
2 - 6 foot 2 inches
3 - pretty strong
4 - advanced beginner
5 - spearfishing in strong currents (mix of slow surface cruising and heavy kicking to get home !)
6 - spearfishing
7 - aspetto in the range 3m to 15m

Any advice ? C25's ?


(Oh - lots of granite so I was also considering Waterway's / fibre fins)
I don't thnik the use of C4 the best choice, I would recommand WaterWay...
for that depth plastic fins like you got should do the trick.Even i don't see the benefits of gara 3000 up to 15 meters. After 4-5 kick i almost cover 15 meters at negative at 10 meters. Way up may take 7-9 kicks.

Hovewer if you want to upgrade waterway seems more logical than C4s.
Ok Peter:
So let me know what you think would be best for me:

1. 60Kg
2. 1.72 m
3. not particularly strong but am planning to get more muscles (for freediving reasons only), especially in the legs.
4. Technique can't be very good, as I have always fined the way I felt it, nobody never told me anything. don't really do any dolphin kick except in the pool maybe.
5. I don't mind the speed, whatever will bring me the farer...
6. mainly constant weight. I might go for a monofin for dynamic, and maybe for CW as well later. I might use them after a wile for deep spearing.
7. I am considering sinking most of the way down and fining mostly the way up

At the moment I am freediving in the range of -40m with plastic fins

Thanks for the advice
Rémi, portinfer;

It's very hard to give advices about fins but I can give you my own data and what fins I think is too hard and too soft:

1. 75kg
2. 178cm
3. Trained athlete but not very strong
4. Kicking whith almost straight legs and from the hip (when using flutterkick)
5. from slow to sprint
6. recreational freediving
7. slow descent fast ascent

Too hard:
Imersion Esclapez black
Cressi Gara 3000
Cressi Gara 2000hf
Sporasub dessault plastic
C4 Falcon 30
all OMER plastics I've tried

Too soft:
Sporasub radical -it bend too near the toes

Good stiffness:
C4 Falcon 80 (model year -2000)
Cressi Gara2000, (but they have no angle so I don't like them)

If I should buy new blades from c4 I would go for the f25 or the f15, but try first.

Best of all for both of you is
1. Get your techniques filmed.
2. Fine tune it to the max with softer rubber fins
3. try every fin you can.
4. Buy the optimal fins

For me it took 5 years of mistakes and spent money on different fins to come to my conclusions. If I had worked with my technique very intensive in the beginning and then go for the fins I had minimized money and time.:waterwork

I hope this help you

And one important thing; the footpockets shall be tight to get the best performance. The footpockets fit can ruin a fins performance. Best is the footpockets that are fitted on monofins with open heel. For max performance choose fins with an open heel solution, the worst is that theese pockets lack in comfort.:(
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