Grade 5 is actually quite common, it's also called Ti6Al4V.
Yeap,it is .
But ...
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What is an OmniVap?
The OmniVap is primarily constructed from Grade 2 titanium. It’s key feature is its variable flow air/vapor ratio, which is easily adjusted by rotating the mouthpiece. This provides a near infinite range of adjustments for the flavor profile of your vapor. This provides a near infinite range of adjustments for the flavor profile of your vapor.
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https://www.dynavap.com/about
Cheers.