Our production team consists of active and former finswimmers, who have experience in fins production more than 25 years.

All our fins for finswimming, freediving, lifesaving, spearfishing, surf, and underwater games are professional and custom made.

Our company is international and has manufactories in different parts of Europe. We organized our work in such way that each stage of fins producing takes place where it is the most optimum.

For our fins we use high quality fibreglass and hand-laminated multilayer mixture of resins and other chemicals, which are vacuum processed in special moulds. Fibreglass is the material tested for years in the highly resistant fins and monofins with widely and well-known results in international competences.

Proof lies in the results: National Championships, World Championships, and World Records, which have been accomplished by athletes using Leaderfins.

We are one of the few companies who give manufactory guarantee for all products for a year. You can see us at almost all great championships.

We are always open for your questions.

Immersion Freedive academy and shop

Our mission is to provide you world's best fins for your sports & challenge, fun & adventure. All our fins - for freediving, rescue, spear fishing, body surf, fin-swimming - are custom made, produced according to your individual needs and wishes. The combination of product innovation, specifically developed materials amd long-experienced workmanship makes our fins really alive and powerful - which you can feel in their high technical perfomance and durability.

Our vision is to be constantly in development - as you in your performance. E.g. currently we work on refining the materials and very soon we will be able to offer you fins in carbon - for freediving, rescue and spear fishing. We are also working on new models and types - right now for UW-rugby for example. We work in closest co-operation with world's leading sportsmen and experts for testing our products.

Who we are? Our production team consists of former fin-swimmers. Our production manager is 2 times world champion in underwater orientation, having experience in fins production for almost 15 years. Until the beginning of year 2003 whole our team worked under Sebak Ltd, but since March 2003 we started our independent way as SpecialFins Ltd.

As materials for fins we use hand-laminated multilayer mixture of resins and other chemicals, which are vacuum processed in special moulds and fibreglass from Denmark, specially developed for our fins. SpecialFins Ltd. has delivered its high quality fins to more than 30 countries all over the world.

Are you interested? We are happy to provide you with our flexible and quick service. Come up with your ideas and we'll help you to make the real! We are always there to provide you advice and service.

Immersion Freedive academy and shop

C4 was founded in February 1986 to create and produce with carbon fibres the designs of Marco Bonfanti, founder and driving force of the company.

The first pieces created were fork frames for racing. These were created by using a unique system for pressing carbon structures, named NJC, No Joint Construction, which enables the creation of hollow pressed structures without joints.

The C4 frames made their debut in cycling competitions in May 1987, when the Bianchi racing team took part in the time lap of the Giro d’Italia (Cycling Tour of Italy) equipped with fork frames designed and produced by C4.

These frames were a world preview for some characteristic components, such as the entire carbon monocoque construction without joints, the frame without saddle pipe, the adjustable seat pin all dimensions with three unique frame sizes, and the carbon monocoque front fork. The first spoke wheels in the world designed by C4 made a stunning display at the Bike Fair of Milan in October ’87, on a bike presented by a famous Italian manufacturer in collaboration with a car firm.

The 1992 Cologne Fair saw an innovative frame consisting of front carbon monocoque quadrilateral and rear aluminium pipes directly glued during pressing. C4 has used this technique for all gluing on frames since 1989.

In 1992, C4 realized the first carbon fibre bi-fins in the world, revolutionizing the apnoea diving community with its exceptional performance.

1992 was the year of the first world record in apnoea at constant weight of the C4 bi-fins set by Umberto Pelizzari. Since then, following further development, these bi-fins have been so important for records in apnoea at constant weight that it equips male and female record holders in this sport.

At the 1993 Milan Fair, C4 presented a new bike, model 47.61, which is the first high performance racing bike to cover all cyclist sizes from 47 to 61, by using a specific design for the whole bike. In 1994, C4 sponsored a leading team of professional racers, Polti including Gianni Bugno and Ivan Gotti. Following this experience the CLASS frame was created and presented at the 1996 Cologne Fair, being the first to overcome the actual kilogram weight for a frame.

The main target of Marco Bonfanti, owner and designer of C4, is to create high performance products, which explains the success of his diving FALCON bi-fims, introduced in 1998. Owing to a rich experience gained in record-breaking along with the carbon fibres, they now come in different sizes from those that have been standard over many years, increasing efficiency by over 20% compared to the previous carbon models: this result has been confirmed by new incredible world records.

Immersion Freedive academy and shop