What are these fuel line fittings?

China Custom Diesel Fuel Line Fittings Manufacturers, Suppliers - Stainless Steel Diesel Fuel Line Fittings - JIAYUAN

Home brew budget nylon fuel line tool - LS1TECH - Camaro and Firebird Forum Discussion

The Earl's Vapor Guard product line has been expanded to include O.E. fuel line quick connect fittings. These adapter fittings allow an easy way to re-use existing OEM fuel rails, fuel filters, and other components when doing an engines swap, or upgrading to Vapor Guard (or other AN Plumbing). Each fitting has a -6 AN Male Flare, and a metal retainer nut for a secure leak-free connection to the 5/16 in. or 3/8 in. SAE style fuel tube. Constructed from 6061 T6 aluminum w/ black anodized finish.

Earls O.E. Fuel Line EFI Quick Connect - 751166ERL

PACE Performance - PAC-632053 - Pace Pac Pump to Carb Fuel Line Package, SBC with Holley 4150

5.3 LM7 w/ Fuel Return Line routing

Fuel Line Fittings Installation Tool Kit, Aluminum Alloy Rotary Fuel Hose Connection Bracket For 4AN 6AN

Broken fuel line clip - Ford Truck Enthusiasts Forums

Help with fuel leak please

Fuel Line, Oil Line, Sediment Bowl Connector with Female Fitting - The Brillman Company

Adding a return fuel line fitting to your fuel tank is simple with the no welding required FAST® EZ-® -6AN Fuel Return Line Fitting.

EZ-EFI -6AN Fuel Return Line Fitting

An installation kit to plumb the fuel lines from the splitter valves to a Cummins engine with composite hose and compression fittings. Kit Includes

Cummins Fuel Line Plumbing Kit - Compression Fittings & Composite Hose

Fuel-It replacement lines SupraMKV - 2020+ Toyota Supra Forum (A90 MKV Generation)