Fourth Element Arctic X Men's One Piece
Use these size guides to find the best fitting size for your Fourth Element Undersuit garments for you. Please be aware that not all sizes are available in all products. See individual product pages for size availability. Please contact us if you have any questions or require further assistance with sizing.
Please note that not all sizes are available in every garment.
Please note: Fourth Element sizes are designed to be snug. For a more comfortable fit, we recommend considering a size up than your usual dress size.
Find below Men's, Women's and Sock Size Charts:
Mens's Sizes
| Size | Height (cm / in) | Chest (cm / in) | Waist (cm / in) | Inside Leg (cm / in) |
|---|---|---|---|---|
| X Small | 165–172.5 / 65–68 | 76–86 / 30–34.2 | 58–68 / 23–27 | 76–80 / 30–31.5 |
| Small | 170–178 / 67–70 | 86–96 / 34–38.2 | 68–78 / 27–30.5 | 79–83 / 31–32.5 |
| Medium | 175.5–183 / 69–72 | 96–106 / 38–42.2 | 78–88 / 30.5–34.5 | 82–86 / 32.5–34 |
| Large | 180.5–188 / 71–74 | 106–116 / 41.5–46.2 | 88–98 / 34.5–38.5 | 85–89 / 33.5–35 |
| X Large | 185.5–193 / 73–76 | 116–126 / 45.5–50.2 | 98–108 / 38.5–42.5 | 88–92 / 34.5–36 |
| XX Large | 190.5–198 / 75–78 | 126–136 / 49.5–54.2 | 108–118 / 42.5–46.5 | 91–95 / 36–37.5 |
| XXX Large | 195.5–203 / 77–80 | 136–146 / 53.5–58.2 | 118–128 / 46.5–50.5 | 94–98 / 37–38.5 |
Women's Sizes
| Size | Height (cm / in) | Chest (cm / in) | Waist (cm / in) | Inside Leg (cm / in) |
|---|---|---|---|---|
| XX Small | 160–168 / 63–66 | 68–76 / 27–30 | 51–59 / 20–23 | 71–75 / 28–29.5 |
| X Small | 162.5–170 / 64–67 | 74–82 / 29–33 | 57–65 / 22.5–25.5 | 73–77 / 28.5–30.5 |
| Small | 165–173 / 65–68 | 80–88 / 31.5–35 | 63–71 / 25–28 | 75–79 / 29.5–31 |
| Medium | 167.5–175 / 66–69 | 86–94 / 34–37 | 69–77 / 27–30.5 | 77–81 / 30.5–32 |
| Large | 170–178 / 67–70 | 92–100 / 36–40 | 75–83 / 29.5–32.5 | 79–83 / 31–32.5 |
| X Large | 172.5–180 / 68–71 | 98–106 / 38.5–42 | 81–89 / 32–35 | 81–85 / 32–33.5 |
| XX Large | 172.5–180 / 68–71 | 104–112 / 41–44 | 87–95 / 34.5–37.5 | 81–85 / 32–33.5 |
Sock Sizes
| Unisex Sizes | UK | US | EU |
|---|---|---|---|
| XS | 3-4 | 4-5 | 35-37 |
| S | 5-6 | 6-7 | 38-40 |
| M | 7-8 | 8-9 | 41-42 |
| L | 9-10 | 10-11 | 43-44.5 |
| XL | 11-12 | 12-13 | 46-47 |
| XXL | 13-4 | 14 - 15 | 48-49 |
If you're serious about cold-water diving, a one-piece undersuit is hard to beat — and the Fourth Element Arctic X Men's One Piece is about as good as it gets. One garment, head-to-toe coverage, no gaps between jacket and leggings, and no cold water finding its way to your lower back mid-dive. It's the kind of kit that makes you wonder why you ever bothered with separates.
Built from recycled materials with a DWR water-repellent outer shell and a warm fleece lining, the Arctic X One Piece delivers serious thermal performance without the bulk. The full-length two-way zip runs the length of the front, making it straightforward to get on and off even in a cramped dive boat — and if you need a pee valve fitted, it's ready for one straight out of the box. Articulated sleeves and knees, combined with 4-way stretch fabric, mean the suit moves with you in any position, especially in horizontal trim where fit really counts.
Thumb loops and single-layer foot stirrups keep everything in place while you're pulling on your drysuit, and the low-bulk ankle design means no fighting with excess fabric around your feet. Pockets give you quick access to small essentials, and subtle reflective detailing adds low-light visibility when you need it. Certified to Global Recycled Standard (GRS), Oeko-Tex 100 and Bluesign standards, plastic-free packaged, and machine washable. Available in both regular and short leg lengths.
Key Features
- Full one-piece construction — eliminates cold spots and gaps between separate top and bottom layers
- Exceptional thermal protection with minimal bulk — purpose-built as a drysuit undersuit
- Full-length two-way zip for easy donning and doffing
- Pee-valve ready
- DWR water-repellent outer layer to shed moisture between dives
- Soft fleece lining for warmth without added weight
- 4-way stretch fabric for unrestricted movement in any position
- Articulated sleeves and knees optimised for horizontal trim
- Thumb loops to keep cuffs in place while donning
- Single-layer foot stirrups — slim ankle profile fits easily under a drysuit
- Integrated storage pockets
- Subtle reflective prints for low-light visibility
- Made from recycled materials — GRS, Oeko-Tex 100 and Bluesign certified fabrics
- Plastic-free packaging
- Machine washable
Technical Specifications
| Colour | Black |
| Weight | 1.30 kg |
| Outer Shell | 85% nylon, 15% elastane |
| Inner Shell | 95% polyester, 5% elastane |
| Lining | 81% recycled polyester, 12% elastane, 7% polyester |
| Certifications | Global Recycled Standard (GRS), Oeko-Tex 100, Bluesign |
| Packaging | Plastic-free |
| Care | Machine washable |
FAQ
One piece or separate jacket and leggings — which is better?
It comes down to personal preference and how you dive. A one piece gives you seamless coverage with no gap at the waist — great for colder water or longer dives where you don't want any weak points in your thermal layering. Separates give you more flexibility, particularly if you run warm on top but cold on the bottom (or vice versa), or if you want to mix and match layers for different conditions. Both systems work well — it's worth having a think about how you typically dive before committing.
Is the Arctic X One Piece suitable as a standalone undersuit?
Yes — it's designed to work as a complete drysuit undersuit on its own in moderately cold to cold water. For very cold or technical dives, some divers choose to add an additional base layer underneath for extra insulation.
What is a pee valve and does this suit come with one fitted?
A pee valve (also known as a p-valve) is a discreet relief system that allows divers to urinate without removing their drysuit — useful on longer dives or in very cold water. The Arctic X One Piece is pee-valve ready, meaning it's designed to accept one, but it does not come with a valve fitted as standard. Fitting is typically done by a drysuit technician.
Can I wear the Arctic X One Piece under any drysuit?
Yes. The low-bulk construction and slim ankle profile are specifically designed to fit under standard drysuit boots without adding excess volume. The single-layer foot stirrups keep everything tidy during donning.
How do I care for the Arctic X One Piece?
It's machine washable — just follow the care label instructions. Avoid fabric softener, as it can degrade the DWR water-repellent coating over time. If the DWR performance drops off after extended use, it can be refreshed with a DWR re-treatment spray.
VIDEO CONSULTATIONS NOW AVAILABLE: We're bringing our highly experienced and knowledgeable staff to you with live-streaming consultations. If you need help choosing the right bit of kit or the best size before buying or even advice on whether a purchased item is the right fit for you, then book yourself a consultation appointment.
We offer free tracked UK standard delivery on orders over £50 (Excluding Weights and Cylinders, as they must go on a separate service to your order)
Standard UK delivery and Next Business Day UK delivery rates are calculated at checkout and offers a number of courier options for maximum convenience to you.
International shipping rates depend on items, shipment weight and destination. Shipping costs are calculated at checkout.
Estimated delivery times are shown during checkout and reflect your chosen delivery method. More Details
60 Day Stress Free Returns
If you change your mind, it doesn’t fit, or you become inflicted with buyer’s regret - that's OK!
Mike's Dive Store offer an extended returns policy of 60 days - so you can be rest assured if the suit, piece of diving equipment or gift doesn't suit then just send it back, and we will either exchange it or offer a full refund less any postage costs. Too easy!
Please note that there are some special order items on our website that will be subject to a 20% re-stocking fee, but we will let you know about these items before we 'special order' them so that you are aware of this. If this is the case we can always help with correct sizing so that we minimise the risk of return. More Details
Returning To Chiswick Store
We want to make your shopping experience as seamless and enjoyable as possible, even when it comes to returns. That’s why we offer hassle-free returns at our Chiswick store. But there’s more—when you visit to make a return, you can also pre-order items to be available for collection. This means we’ll have a range of sizes ready for you to try on, ensuring you find the perfect fit before leaving the store.
Shop with Confidence, Wherever You Are
To make things even easier, we offer complimentary video consultations with our expert team. Whether it’s before or after your purchase, our specialists can guide you through sizing, fit, and styling—all from the comfort of your home. It’s like having your own personal VIP shopping experience, tailored just for you.
From returns to reorders, we’re here to help you find exactly what you need with zero stress.
Book Video Consultation: Book Now
We offer the option for customers to choose ‘Pickup in store’ as a shipment method, allowing your order to be picked up from our Chiswick store at a time and date that works for you (within our business hours). The process is really easy, but we'll run through it here:
Step 1 - Add products to your cart:
Browse our vast selection of diving and snorkelling equipment, adding the kit you want to your cart.
Step 2 - Head to your cart:
Click on the cart icon to see a summary of the items you are about to purchase.
Step 3 – Review Your Order and Proceed to Checkout:
Once you're satisfied with the items in your cart, you can add a note to your order under the "Order Summary" section if desired. When you're ready to proceed, simply click "Checkout" to complete your order.
Step 4 - Customer Information:
If you have a Mike's Dive Store account, simply log in to autofill your details. If not, enter your email address, select ‘Pickup in Store,’ and then click ‘Continue to Payment’ to proceed.
Step 5 – Payment & Billing Details:
Select your preferred payment method and enter your payment information. Below, provide your billing details. If you're logged into your account, please double-check that your billing and contact information are up to date.
Step 6 – Review Order:
After entering your payment details, click ‘Review Order’ to proceed with placing your order. You will receive an email confirmation with your unique order number. We will notify you when your order is ready for collection, usually within 4 hours or sooner during our opening hours (Monday to Saturday, 10 AM to 6 PM). Please note that our hours may vary during the Christmas and New Year periods.
Our London Store Information:
Address:
Mike's Dive Store, 113 Power Rd, Chiswick, West London, W4 5PY
Telephone:
Local: 01202 037162
International: 0044 1202 037162
Email:
All Enquiries - support@mikesdivestore.com
Store Opening Times:
Mon - Fri: 10am - 6pm
Sat: 10am - 5pm
Sun: Closed
Need Help?
Our expert diving team is here to assist with your order, sizing, or product selection. We're divers ourselves, ready to support you!
Chat Hours:
Monday - Friday: 09:00 AM - 05:50 PM GMT
Prefer a call back? Just request it through the chat bubble!
Store Location
Mike's Dive Store
113 Power Rd, Chiswick, West London, W4 5PY
Store Hours
Mon - Fri: 10 AM - 6 PM
Sat: 10 AM - 5 PM
Sun: Closed
Bank Holidays: Store & Warehouse Closed (no dispatch)
Online Video Consultations
Unable to visit us? Book a live video consultation for tailored advice on equipment, fitting, or specialized gear. Get expert guidance from our team, face-to-face. Book Now
For more answers, visit our FAQs.