The Complete Guide to Freediving Neck Weights

The Complete Guide to Freediving Neck Weights

If you have spent any time in a pool or out at a buoy, you have probably watched a more experienced diver glide along perfectly flat while you fight to keep your legs from sinking. Often the difference is not lung capacity or technique — it is where the weight sits. A neck weight moves a chunk of your ballast off your waist and up towards your shoulders, and for a lot of disciplines that small shift makes a real difference to your trim and your comfort.

I am Michelle, and I run Zen Freediving. I am not going to tell you a neck weight will fix your dive overnight, because it will not. But I will tell you honestly what each one we stock is actually for, where it works, and — just as importantly — where it does not. We carry three, and they are genuinely different tools for different jobs.

What a neck weight actually does

A weight belt sits at your hips. That is fine for a lot of diving, but it pulls your lower body down, which is exactly the opposite of what you want when you are trying to lie flat in a pool or stay streamlined on a descent. A neck weight shifts ballast up towards your head and shoulders, which helps level you out. For pool disciplines — dynamic and no-fins especially — that higher placement is the whole point. For depth divers, the appeal is usually streamlining: less bulk around the waist, weight tucked close to the body so nothing shifts or drags.

Here is the honest caveat before we go any further: a neck weight is a supplement, not a magic trick. You still need to dial in your overall weighting, and you should always do that gradually and within your training limits. Over-weighting around the neck is not something to experiment with casually.

The one distinction that matters most: pool versus depth

Please read this part carefully, because it is the question I get asked most and the one most worth getting right:

• The Lobster 2.0 Neck Weight is for POOL freediving ONLY. It is NOT suitable for depth or open-water freediving. Do not take it down a line. It is built for pool training — dynamic, no-fins, static work in a controlled environment.
• The Alchemy Silicone Neck Weight and the Flex Neck Weight are both suitable for BOTH pool AND depth. If you want one neck weight that follows you from the pool to the buoy, those are your two options.

If you only remember one thing from this guide, make it that. Now let us go through each one.

Alchemy Silicone Neck Weight — the streamlined all-rounder

The Alchemy Silicone Neck Weight is the one I reach for when someone wants a clean, low-fuss setup that works everywhere. The lead core is encapsulated in aerospace-grade, medical-grade silicone, so it moulds flush against your neck and shoulders and stays put — it does not shift on the surface or bounce on the way down. Alchemy's silicone grips bare skin as well as a smooth or nylon-lined wetsuit, and it shrugs off both chlorine and saltwater, which is exactly what you want from something that lives in your dive bag.

Suitable for both pool and depth. Depth divers like it for the streamlining; pool athletes like it for being tidier than a belt.

One thing worth understanding about how Alchemy rates these: the figure in the variant name is the negative buoyancy of the unit, not the raw scale weight — the actual weight on a scale is marginally higher. You choose the configuration to match your suit thickness and your own buoyancy.

Sizes and weights

• 40 cm — 0.93 kg (Black or White)
• 40 cm — 1.10 kg (Black or White)
• 40 cm — 1.23 kg (Black or White)
• 45 cm — 1.40 kg (Black or White)

This is a fixed-weight design, so pick the negative buoyancy that suits your setup rather than expecting to adjust it later. If your weighting needs change a lot session to session, the Flex below may suit you better.

Flex Neck Weight — adjustable, and the one I most often recommend to start

The Flex Neck Weight is our own Zen Freediving design, and it is the one I point most newcomers towards — not because it is the fanciest, but because it grows with you. It is a 3 mm neoprene pouch that sits comfortably across the back of the neck, with a modular pocket system so you can dial your ballast in precisely. There are five pockets, each taking up to one 250 g and one 500 g plate, giving a total range from 250 g all the way to 3.75 kg in tidy 250 g increments. The strap adjusts from 42 to 53 cm to fit different necks, and there is a quick-release buckle for fast, safe removal.

Suitable for both pool and depth. It is comfortable enough for long sessions without chafing, and versatile enough to follow you from the pool to open water.

The reason I like recommending it: you are not locked into one weight. As your training and buoyancy change, you just move plates around instead of buying a whole new weight.

How you can buy it

• Complete sets, 2.25 kg and above, in Blue, Green or Black — priced by how much ballast they carry, stepping up in 250 g increments, with the heaviest set naturally sitting at the top of the range
• Pouch only, no weights, in Blue, Green or Black — the cheapest way to get into the system
• Individual plates, in 250 g and 500 g, for topping up as you go

If you already own lead, the pouch-only option plus a few plates is a sensible, economical way in — comfortably the most affordable route to a Flex setup.

Lobster 2.0 Neck Weight — for the pool, and only the pool

Important, so I will say it plainly first: the Lobster 2.0 Neck Weight is for POOL freediving ONLY. It is NOT suitable for depth or open-water freediving. Please do not use it on a line.

With that understood — for pool work the Lobster 2.0 is a lovely piece of kit. It is a modular system that gives you precise ballast control without a full weight belt, positioning weight high so you reduce that feet-first sinking that plagues no-fins and dynamic apnoea. The segmented design lets you fine-tune between dives without rearranging your whole setup, and Version 2.0 has a revised shape that sits more comfortably against the neck and shoulders over a long pool session. It is the most considered of the three for a dedicated pool diver — and also the most expensive, which reflects that.

Sizes (in stock, Black)

• Small full set — 1.5 kg base plus 400 g, 300 g, 200 g and 100 g segments (total 2.5 kg)
• Medium full set — 2.5 kg base plus 500 g, 400 g, 300 g, 200 g and 100 g segments (total 4 kg)
• Small base only
• Medium base only
• Individual segments in 100 g, 200 g, 300 g, 400 g and 500 g, each priced a little higher as it gets heavier

We stock the Small and Medium full sets in black, plus individual segments for top-ups and replacements. If you want the Large set or a different colour, just message us and we will fold you into our next group order. After saltwater use — though again, this is a pool weight — rinse the segments and base in fresh water, dry the connection points before storing, and check the segment attachment before each session.

So which one should you buy?

Here is how I would steer you, honestly:

• You train both in the pool and at depth, and want one weight for everything: the Alchemy Silicone Neck Weight (streamlined, fixed weight) or the Flex Neck Weight (adjustable). Both are pool-and-depth.
• You are not sure of your exact weighting yet, or it changes session to session: the Flex Neck Weight — adjustable in 250 g steps, and you can start with just the pouch.
• You want the cleanest, most streamlined fit for depth: the Alchemy Silicone Neck Weight.
• You are a dedicated pool diver wanting precise, modular control: the Lobster 2.0 Neck Weight — pool ONLY, never for depth.

A quick comparison

• Alchemy Silicone Neck Weight — Pool and depth. Fixed weight, silicone-encapsulated, very streamlined. Sits in the mid part of the range.
• Flex Neck Weight — Pool and depth. Adjustable 250 g to 3.75 kg, neoprene pouch, modular plates. The most affordable way in, especially if you start with the pouch only.
• Lobster 2.0 Neck Weight — POOL ONLY (not for depth). Modular base-plus-segments system, premium. The flagship of the three and priced accordingly, with the Medium set sitting above the Small.

If you are still unsure, send us a message and tell me what you dive, where, and in what suit — I would much rather help you buy the right one once than have you buy twice. Dive safe, never alone, and always within your training.