Robert - the 'off- setting makes the gun essentially a single shot, or a for of a 'bolt action firearm, that has to be manually loaded by working the bolt with each shot. You chamber a round, fire it, then you have to work the bolt manually to load the next shell. The 'off' position just stops the gas from the expended shell from entering the action of the shotgun, to cycle the action.

I think the Off setting make the gun a single shot IE fire manually work the bolt to load the next shell but I suggest that you verify this at SDS Imports phone them at (865) 604-6894.

Robert. I looked at the owners manual which does not explain the off setting (sdsimports.com/v/vspfiles/downloadables/Lynx12%20Manual.pdf). My guess is that it would be used for "Storage". SDS Imports may be able to verify this at (865) 604-6894.