lungtank.com/products/lung-sub-mask
Ok, what's the catch?
Why has it taken until 2023 to invent this?
Ok shxr full face mask aside u xan buy these things without that
Its taken this long for china to make and a lax goverment/ lack of governance i guess.
The whole reason u are meant to have done an accredited scuba course is u can really hurt yourself. These are very small and they may argue that this limits the ability for harm. But if you were to freedive to a decent depth, then breath it all in so u could stay down longer the return to the surface i daresay you could blow out both lungs
Here u go just googled for u.
www.scubadoctor.com.au/scorkl-dangers.htm
Pulmanory barotroma. Making your lungs go pop. Bought to you by the same nation that put poison in baby formula. Advertised on facebook so u know it must be shxt
Select to expand quotemyusernam said..
Here u go just googled for u.
www.scubadoctor.com.au/scorkl-dangers.htm
Pulmanory barotroma. Making your lungs go pop. Bought to you by the same nation that put poison in baby formula. Advertised on facebook so u know it must be shxt
For example:
If you take a breath at 10m, that will double in volume at surface.
At 5m, if your lungs hold 6 litres and you hold your breath to aid getting to surface, that 6L will increase to 9L.
Unfortunately our lungs are pretty fragile and it doesn't take much extra pressure to cause damage
I remember choosing scuba diving as an activity on a Scout Jamboree when I was about 15 years old. I was given a tank, mask and flippers, told to make sure I breath out as I come up so my lungs wouldn't burst, then they pointed to a headland off the end of the beach and told me there was a nice reef to look at it. Off I swam, totally unsupervised, and had a ball. Imagine that happening today!
Bit like a lot of things, if you don't know what you're doing then simply don't do it. 
The catches:
- This is only rated to 3m, and it is more difficult to equalise your ears with a full face mask than a half mask
- The link is to mask only - so the cost is around $500 with the cylinder
- its not great to be playing with filling compressed air cylinders without knowing what you're doing. any contaminants that enter the cylinder that may be benign at ambient pressure can be fatal at depth as the partial pressure increases (eg carbon monoxide, carbon dioxide).
- You won't get the claimed 10 minutes out of it breathing underwater. It is a 3 cubic foot cylinder the same as a Spare Air, which they claim gives you 57 breaths at surface = embolism => death.
underwater.com.au/shop/submersible-systems-spare-air-pack.html
if you do want to go down this path don't buy this, buy a cheaper spare air unit with a yoke adapter and get your local dive store to fill it - the cylinder will be hydrotested to australian standards and you will have clean air. But you will need to have a diving certification to get an air fill.
In short, if you want to breathe compressed air, do a dive course and then you'll appreciate that this is a waste of time and you might as well either just go diving or just go freediving. If you are a vaguely competent freediver you can easily outlast one of these units on one dive, and you don't have to go back to shore and spend half an hour refilling or pay a few bucks to fill it - take a few deep breaths and do it again!
Background - diving instructor, submarine escape instructor and commercial diver.
Select to expand quoteCH3MTR4IL5 said..
The catches:
- This is only rated to 3m, and it is more difficult to equalise your ears with a full face mask than a half mask
- The link is to mask only - so the cost is around $500 with the cylinder
- its not great to be playing with filling compressed air cylinders without knowing what you're doing. any contaminants that enter the cylinder that may be benign at ambient pressure can be fatal at depth as the partial pressure increases (eg carbon monoxide, carbon dioxide).
- You won't get the claimed 10 minutes out of it breathing underwater. It is a 3 cubic foot cylinder the same as a Spare Air, which they claim gives you 57 breaths at surface = embolism => death.
underwater.com.au/shop/submersible-systems-spare-air-pack.html
if you do want to go down this path don't buy this, buy a cheaper spare air unit with a yoke adapter and get your local dive store to fill it - the cylinder will be hydrotested to australian standards and you will have clean air. But you will need to have a diving certification to get an air fill.
In short, if you want to breathe compressed air, do a dive course and then you'll appreciate that this is a waste of time and you might as well either just go diving or just go freediving. If you are a vaguely competent freediver you can easily outlast one of these units on one dive, and you don't have to go back to shore and spend half an hour refilling or pay a few bucks to fill it - take a few deep breaths and do it again!
Background - diving instructor, submarine escape instructor and commercial diver.
You've forgotten about the health benefits from the aerobic activity required to refill the tank yourself with the available hand pump option. 
Fun, police on patrol.
Buy it, don't go more than 3 metres and understand the risks, then have a little fun with it if you think you'll like it.
