Mauro Chiostri (Extrema Ratio)

January 28, 2023

We are excited to interview Mauro Chiostri, a 100% Italian, a knife maker, a co-founder and owner of the brand “Extrema Ratio”, and just a stylish and fashionable person, as the majority of Italians who have it in their blood. Is there any connection between knives and fashion, and what knife should you have in your purse if you are a high fashion model — you will get to know the answers to these and other questions in our interview.

Extrema Ratio interview

The Fashiongton Post: What was the first knife ever owned by you? Was it a gift from anyone or the one you purchased?

Mauro Chiostri: I got my first knife as a gift from my father when I was just a kid. We were living in the countryside near Florence where it was common to carry one in the pocket. It was a traditional knife from our region, a folding knife with the carbon steel blade and a horn handle. Unfortunately, I don’t have that knife with me anymore, though I still have two left by my dad which were similar to the one he gave me.

Maurizio Castrati

F.P.: As we know, you founded the brand together with Maurizio Castrati. Whose idea from the two of you was it initially? And is Maurizio Castrati still being a co-founder of the brand or you are a single owner of Extrema Ratio as for now?

M.C.: Maurizio and I have been friends since school. One day we started thinking that if we would combine our skills and passions, we could create a knife manufacturing company from scratch. Our families were not in the knife business and nobody could help us, so it’s been a long and winding road, but we have reaped what we sowed. Even while we follow different paths now, Extrema Ratio will always keep records of our work together.

Mauro Chiostri interview

F.P.: Do you always carry a knife in your pocket as EDC (Every Day Carry) these days? If yes, which one?

M.C.: Today Italy has very strict laws on knife carry and, unfortunately, I can’t always have one with me in while in the city. However, I live in the countryside, so I’m never without a knife there. My favourite ones are compact folding knives such as ‘BD1’, but I often use ‘Kreios’ and ‘Venom’ too. I always carry one at work, sometimes I also have knives produced by other manufacturers, so that I could study their strengths and weaknesses.

Extrema Ratio interview

F.P.: Do you consider yourself as fashionable?

M.C.: I consider myself as being up to date and having a good taste, which comes naturally in a country that is home to many fashion brands and has an overwhelming artistic heritage.

Mauro Chiostri Extrema Ratio

F.P.: Your favourite outfit for everyday wear?

M.C.: I generally prefer wearing casual clothes, except for special occasions.

F.P.: What was the last thing you cut with your knife today?

M.C.: I opened a package from an online purchase by cutting its tape.

F.P.: The most unusual thing you had a chance to cut with you knife?

M.C.: My friend’s necktie when he got married. Traditionally we use scissors, but that time we hadn’t any.

Mauro Chiostri interview

F.P.: Knife culture and fashion. What connects those two major industries, as you see it?

M.C.: Fashion is one of the greatest forms of expression when it comes to design. Design is also an essential part of many activities that men use to express themselves. Knives are one of those. When design harmonizes with functionality, that’s when you get the best result. Knives blend well in our day-to-day life and even in our most common habits, so I believe that a knife with a sophisticated design should be everybody’s everyday companion, matching the style of who’s carrying it.

Mauro Chiostri interview

F.P.: At what age did you come to knives?

M.C.: I got my first knife when I was six, but my passion awoke later at approximately 25, when I realized that passion could turn into a career.

F.P.: There are many celebrities who collect knives, like for example Angelina Jolie, Sylvester Stallone, Nicolas Cage, Steven Tyler, Ted Nugent, etc. Have you ever had a chance to create some knives for fashion or movie celebrities?

M.C.: I haven’t had the chance yet, but we are working with a Hollywood star now on a project of such a kind. Anyway, our knives were used in many movies and TV series, such as “Mission Impossible III” (Tom Cruise carries a ‘TFS Pilot’ knife), “Lost” (featuring our ‘K1 Dobermann’ knife), “24” (a ‘Fulcrum’ knife model can be spot on Kiefer Sutherland’s jacket), and many other movies.

Extrema Ratio interview

F.P.: Has the knife ever saved your life?

M.C.: Fortunately, it never happened to me.

F.P.: Your favorite knife produced by other brands?

M.C.: There are many, but the only one that hits me everytime I see it is ‘Randall Model 1’.

Mauro Chiostri Extrema Ratio

F.P.: Best type of the knife lock?

M.C.: I think that the Liner Lock system is very practical and functional. However, I do prefer the Back Lock more for its distinct characteristics of solidity. If made with the right proportions, it offers an extremely solid blocking system.

F.P.: Do you sleep with the knife?

M.C.: I do have one near me, but since I have a young daughter I keep it hidden.

Mauro Chiostri interview

F.P.: Best knife for a high fashion model (a girl who’s into modeling) for every day?

M.C.: I would suggest a small one, so that it would fit a purse. Our ‘BD1 R Satin’ would be perfect. A basic one but with its own style.

F.P.: Best knife for self defence?

M.C.: A folding automatic knife, such as our ‘Caimano Nero’. No wonder it has been designed for the special forces of the Italian navy.

Mauro Chiostri interview

F.P.: Your favorite knife made by Extrema Ratio?

M.C.: I’ve changed my mind many times during these years, but today ‘Requiem’ represents the perfect blend of technique, design and usability. I’m struck every time I see it, and this makes me think it could be my favourite.

F.P.: Which knife would you give to your kid as a gift?

M.C.: When my daughter was born I set aside a small folding knife, a ‘BD0’. She’s still a kid but when she will be able to carry one, I hope to see her feeling the same emotion I felt when my dad gave it to me!

Mauro Chiostri interview