Bright-dipped green anodized aluminum bulkhead fittings.
NOTES:
-The 20-0170 6AN ORB with 8.5mm Barb to 6AN Male Bulkhead Fitting was introduced in Radium Fuel Surge Tanks after 2014. It includes a preassembled FKM O-ring and requires a 6AN ORB (9/16-18 threaded hole) with SAE chamfer to be drilled into the mating part for sealing.