Out of all the things that one can possible fear while diving, for me, it’s the possibility of loosing my 4 year old Honda Civic to some lunatic stealer. That’s the main reason why I was never that comfortable with the idea of shore dives. It’s not like I can poke my head out of water and check or chase after the thief while strapped to my BCD, tank and 9kg (19 pounds) weights (very thick wetsuit) … …
I desperately needed to find a solution so I can actually focus on diving. I have enough on my mind already (buoyancy, strong currents, running out of air, runaway ascent, getting lost or separated etc. etc).
Option 1 – Take the car key with you
This turned out to be a no-no. Modern car keys with all the electronics inside just do not mix well with water. I also questioned the water pressure when 30 meters underwater. Better not risk it.
Option 2 – Waterproof bags/cases
Out of all the waterproof bags/cases I investigated, they either don’t have a rating at all, or inadequate rating or rated adequately but had a number of reviews indicated leaks.
One example I considered was this Aquapac KeyMaster.
It is 3-submersible classified, only withstands submersion up to 5m/15ft for at least 30 minute.
So this option is still considered to be unsafe for me.
Option 3 – Key Safe
After giving up on the idea of the waterproof bag, I found the HitchSafe Key Vault.
The idea is a mini safe mounted at the back of your car where you can just leave your keys locked up. Cost approximately AUD$70 on Amazon, but the shipping is expensive. Cost on ebay is AUD$92 including shipping.
Good idea, but too expensive.
Option 4 – Non-electronic replacement key
Sometimes the simplest solution is the best solution and this turned out to be the case. I finally ended up taking my electronic key to the local key maker, and got a replica made (without all the electronics inside) for AUD$30. Probably could get it for cheaper if I shopped around. Called Bunnings Warehouse, they told me ADU$8, but sadly they didn’t have the right blank when I was there.
Now I just pop it in my BCD pocket and take it with me. I guess the only thing I need to worry about now is it rusting!
Fish Number 2
2fishoutofwater 
Thats a great tip. Thanks for discussing this – one of those dive related issues that tends to be ignored! I will be finding out if Bunnings can cut me a “no-frills” key for my new Corolla.
It’s working well for me, no rusting yet.