The smallest 833 bulkhead, sized AN3 for brake and clutch lines, gauge feeds and other low-flow signal plumbing. It gives you a proper sealed pass-through where a line crosses a bulkhead or floor pan, so the hose is never chafing against a raw drilled hole, and the 90-degree body keeps the run tidy against the panel on the far side. Male AN3 flare threads at both ends suit standard AN3 hose ends and adapters, and the extended thread takes a matching AN3 bulkhead nut. Small fittings still need a properly deburred hole — a sharp edge will eventually cut whatever moves against it.