redundant air source

[Shooter]

I have the equipment all d.i.r. approved. I need some info or pics on howand where to attatch to my backplate harness. I might only use a 30 instead of the recommended 40. I do alot of spearfishing and go into tight areas and under ledges. I have the hose clamp with rubber attatchment fo tank. Also where do I store the extra regulator? ???

[LKunze]

Are you referring to diving a single tank rig and then carrying a pony bottle for redundancy?  If so that's actually not DIR approved. If you don't care about the DIR part and you want to carry a redundant pony or bailout bottle like an AL30 or AL40 the best way to rig it in my opinion is to sling it on the left side like a stage.  The hose for the second stage would be rubberbanded to the tank.

[FMT]

A good rig, dive planning, and a good buddy should take care of your needs.
If you still want to carry a stage - here is a good reference on how to rig:

It also has a picture of reg storaage.
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