Wetsuit Dictionary and Terminology

Welcome to the Seventhwave Wetsuit Dictionary.
The place to turn when we use a technical term and you have no idea what it means.

We'll be adding to this list all the time, so if the word or term you are looking for isn't here check back later, or even better, drop us an email and make a suggestion for us to include.

4/3 Thickness

Sometimes known as 4/3 or 4.3

Technically a 4/3 refers to the thickness of a wetsuit with the 4 referring to 4mm: the thickest panels in the wetsuit. The 3 refers to the 3mm thinner panels. So its basically saying: this wetsuit is made from a mixture of both 4mm and 3mm. 

A common misconception is that a 4/3 means your whole suit is made from 4.3mm neoprene.

Generally in a 4/3 wetsuit the 4mm area is placed in an area to give the user maximum warmth generally in the chest and torso area. And the 3mm areas are strategically placed to give the wearer the best comfort and flexibility.

But this is not a hard rule, some manufacturers will make 4/3 wetsuits with the majority of the wetsuit is 4mm and only a small section is 3mm i.e. the shoulders. Here at Seventhwave we can tailor an option to suit you, a popular option is having 4mm from the chest to the legs and 3mm in the arms.

4/3 is a term often used by surfers as a way to describe a winter grade wetsuit no matter what the thickness. 

Eg: Surfer 1: Brah, are you wearing your 4/3 already? Surfer 2: I live in Dunedin so I wear it year round!

Blind Stitch

Blind stitching is used when a seam needs to be waterproof. Perfect for our winter wetsuits.

Sometimes we refer to blind stitched seams as G&S or G+S which means glued and (blind) stitched or glued and sealed.

All our winter models include Glued and Sealed seams. This means that all seams are double glued and butted together to create a seal. They are then given time to completely dry and then comes the actual blind stitching. 

The actual blind stitch is created by sewing machine, it uses a curved needle and does not penetrate all the way through the piece of neoprene. This technique creates a strong seam without compromising warmth.

Chest Zip

Also known as a Zip Bib, and sometimes shortened to CZ or ZB.

The chest zip wetsuit was developed for two main reasons: 1) to reduce cold water leaking through the metal zip in the back of a wetsuit and through the neck closure. and 2) to increase flexibility and comfort. By removing the rigid zip that runs down the spine the back panel stretches more naturally.

How does it work? A chest zip wetsuit has a super stretchy opening at the top of the shoulders that you climb in, and an attached bib and collar that is fastened by a small zip high up on the chest.

A chest zip wetsuit is much warmer, it has a firm one piece collar that provides a great seal around your neck and you don’t get water flushing through a pesky zip at the back.

At first a chest zip is more difficult to put on and take off but with good technique it adds a number of benefits back zip wetsuits don't have.


Sometimes known as Custom

In the Seventhwave universe, a Custom-Fit refers to a wetsuit that has been made specially to fit a customer.
In some cases, a Custom-Fit Wetsuit will be a major sizing change where every panel will need some sort of alteration. But others might only need one or two-minute changes. Overall we've found that approximately two-thirds of people benefit from some sort of alteration.

Learn more about our Custom-Fit service on our page here.


Hot Top

A Seventhwave Staple and one of our favourite products. It has been a Seventhwave favourite for at least 15 years.

Made from 0.5mm Yamamoto Limestone Neoprene, with an exposed Titanium lining for super warmth. Basically it’s a really thin Top that can be worn by itself when its warm or underneath a wetsuit when its cold. The beauty of hot tops is that while they are thin and lightweight, they are very very warm

We make several different style Hot Tops and vests here at Seventhwave and have also branched out into shorts and pants too.


Limestone is probably the coolest thing we offer. In a nutshell, all our neoprene is made from limestone. Yeah it's made from rocks.
Other neoprene is made using dirty old oil, but in Japan, Yamamoto corporation cleverly devised a way to make neoprene from Limestone chips.
Why should you choose Limestone neoprene over Oil based neoprene?
Limestone neoprene has a high micro-cell structure. These are independent closed cells (bubbles basically) within the neoprene that are packed together at an extremely high density. Oil-based neoprene has a cell penetration of 60-70%, whereas limestone neoprene has a 94% cell penetration. What this means in simple terms is that limestone neoprene has a lot more air bubbles inside the rubber than other brands (over 30% to be exact), and is way less dense than oil-based neoprene.

Because of this micro-cell structure, limestone neoprene provides several serious distinct advantages to the functionality of wetsuits compared to the traditional oil-based neoprene:
  • It is impermeable
  • It is lighter in weight
  • It is warmer
  • It is more durable
  • It is stretchy

Our neoprene ROCKS


A wetsuit with short arms and short legs, usually cut above the knee and above the elbow. Spring suits are usually thinner than steamers, either made in 3/2 or all 2mm thickness.

 A variation of the spring suit has long sleeves and short legs, often called a “long sleeve spring” or sometimes a “monkey suit”. The name spring, originally comes from warmer climates, where in springtime the water would warm enough to allow surfers to wear a short arm and leg wetsuit. However in New Zealand it’s vary rare to wear a spring suit in springtime and they are reserved  for summertime.


A full length wetsuit, arm length finishes at the wrist, leg length finishes at the ankle.

Why is it called a steamer? During our research, we found 2 reasons why a full length wetsuit could be called a steamer. 1) a term coined from Steamer Lane, a famous surfing location in Santa Cruz, California which was the birthplace of the surfing wetsuit. 2) Steamer was the name given to full length wetsuits because, when the wetsuit was removed (after being in the water) steam was pouring off the wetsuit. 

Here at Seventhwave, we don't really mind why it was called steamer, but this has become the industry standard. But, what really matters is that Steamers give you full body cover and are the warmest option. especially when combined with sealed seams (more on that in another post).



Sometimes referred to as 7000 or MR7000


We use a number of different types of neoprene here at Seventhwave. Superstretch is probably the coolest type we use. The name says it all: it’s really stretchy. Of course it’s Yamamoto’s limestone neoprene, and being a lighter material it means performance is increased in both warmth and flexibility. 

While other brands of neoprene can be made to feel super “soft” it often stretches after a few seasons and will end up being a size or two larger than when it was new. Our Superstretch neoprene is both soft and has what we call ‘memory’ – meaning out wetsuits told to your body shape and doesn’t get loose over time.

Our Siren and Enduro models both have Superstretch neoprene in the arms and shoulder panels, while our Max model is made entirely from Superstretch – giving our suits amazing elasticity, memory, and multi-directional stretch capacity.

Titanium 2.0

We throw the term Titanium around a lot here at Seventhwave, "Titanium lined this", "Titanium Hot Top that". So here's some nerdy information about our secret weapon...

Titanium Neoprene was pioneered by the Japanese Yamamoto Corporation in the 1980’s (also the innovators of limestone neoprene), ‘Titanium’ is the process of applying a thin Titanium Alpha metallic alloy coating to the neoprene surface prior to the bonding of the outer jersey fabric, and is designed to reflect heat. Once it has been applied to neoprene it looks like a coating of silvery-grey paint.

How does it help me though?: As soon as you enter the water, the heat from inside your wetsuit wants to escape and dissipate. This is called thermal diffusion. As it tries to escape, the thermal heat hits the Titanium-lining that then reflects the heat back towards you, continually. In fact, every time you move, paddle, or expel energy, more heat is created inside your wetsuit and reflected back to you—increasing heat retention by an amazing 40%.

The great advantage is that you can wear a much thinner, lighter wetsuit than ever before without compromising warmth, meaning you can beat those cold water blues and leave those old-style, traditional, thicker wetsuits in the dusty closet where they belong! The thinner the suit, the more flexible you are.

And now, all titanium lined products we make, feature Yamamoto's new Titanium 2.0 (ti-2.0) which is even warmer. It basically has twice the amount of titanium lining (this increases the reflectability, keeping you much warmer.

Zirconium or Aero Zirconium

Abbreviated to AZ, ZR or Zirc

Zirconium in Seventhwave’s wetsuit application refers to a lining on the inside of a wetsuit, this replaces the standard nylon inner lining.

Its bright orange and looks like a fluffy polypro type material, but Zirconium is more than a fuzzy lining. It also packs a whole bunch of tech. Zirconium in it’s raw form is actually a metal, and its physical and chemical properties are very similar to Titanium and is highly resistant to salt water, perfect for wetsuits. Yamamoto’s internal research centre has confirmed that Zirconium improves thermal retention more than titanium.

Aero Zirconium, is composed of 2 types of yarn: Hollow fibre and Zirconium fibre.
- The Hollow fibre contains air, making it lighter and a better insulator, essentially creating an extra air pocket between you and the water.

- The Zirconium fibre yarn has the ability to reflect infrared light transmitted from your skin back onto the body, creating double the warmth between skin and the fabric.

As a result, this combination feels dry when submerged in water.

In a nutshell Zirconium is a fluffy, wool-like material that is extremely warm and fast-drying.