TEST: EPSEALON IMPULSE G2 RED  

100% CARBON FINS - NEW 2016

The IMPULSE G2 fins have been designed by EPSEALON for spearfishing and are available in three versions: RED hard, ORANGE medium and BLUE soft. The blades are designed to fit the EPSEALON foot-pocket made in thermo-rubber and are already glued to the them when they are sold. These fins offer the advantage of a double water canalisation thanks to the presence of small flaps on the end of the blade and to the grooves on both sides of the foot-pockets. This provides a better grip on the water, avoiding them to drift during flexion.

The fins are made of pre-preg T300-3K carbon fibre but before jumping to any conclusion we should first understand what these acronyms mean. Carbon is a composite fibre obtained by weaving filaments thinner than a human hair in a tissue that can be unidirectional or not. Manufacturers have given us over the years several acronyms like T300, T700, T800 and T1000 while marketing has been convincing us that 1000 is better than 700 and so on. In reality, the evaluation of the carbon fibre must be done in consideration of different variables and especially what use they are meant for, that is, the type of stress that has to bear and in which way.

In regards to the value followed by the letter K, it refers to the number of filaments composing a single fibre while with T300, 700, etc. they refer to the type of fibre that differs for properties of resistance and elasticity. Without going through very specific engineering terms it can be said that as the number after T increases, the resistance is higher but on the other hand the elasticity decreases. For instance if a tissue in T1000 is used to make a fin blade, such a material will probably not be performing as a T300 or T700, without considering the increased related costs. After these considerations it can be understood as, for example, some manufacturers of carbon fins have decided to use the two abovementioned fibre types to produce a single product combining the main characteristics of both materials.

As we said carbon fibre is a material consisting of tissue and resin, and pre-preg is a term indicating that the tissue is purchased by fin manufacturers already impregnated with the necessary resin. The advantage of this type of carbon is that the resin is distributed uniformly on the carbon tissue with processes that allow for example to avoid the presence of small bubbles, which represent potential points of failure. Therefore also the properties of the resin and the way in which it is applied affect the overall performance of the final product.

The G2 have an inclination of 22 ° which, thanks to the EPSEALON foot-pocket is fully exploited. The front tip has a tradition dovetail design. The sizes are the following: width 19cm, length 92cm (overall). The carbon fibre blade itself instead measures 80cm in length and provides a thrust surface which measures 62x19cm.

By observing the blade with a certain angle it is possible to note how the fibres are arranged. Towards  ¾ of the length, there are 2 sections with different thickness. This helps to avoid stiffening the blade and stress too much the ankles.

This fin is ideal for deep diving, because its reactivity allows you to save energy when operating at more challenging depths. However, the fact that it is slightly shorter than the other models of fins makes it comfortable while swimming on surface. It’s a very nervous fins that responds well to the first kicks on the bottom when heading to the surface but it is definitely suitable for trained and demanding spearos. The weight of a single fin (foot-pocket+blade) is a few grams less than a kilo. They are sold in a handy nylon bag.