AN Fitting & NPT Thread Size Chart - AN-3 to AN-20 Hose & SAE Thread Sizes

This document is a two-part plumbing/fitting reference chart. The top section is an AN (Army-Navy) Fitting Thread Size Chart presented as a yellow table with three columns: AN Size, Hose Size, and Thread Size. It covers AN sizes -3 through -20, matching each to its equivalent hose size (3/16 through 1-1/4) and SAE thread specification (3/8-24 SAE through 1-5/8 SAE). Below the table, blue graphics visually depict the relative physical sizes of -16, -12, -10, -8, -6, -4, and -3 fittings. The lower section is an "NPT" (National Pipe Thread) Thread Size Chart in a cyan table listing pipe thread sizes 1/8 through 1, their threads per inch (27, 18, 18, 14, 14, and 11-1/2 respectively), and inside diameters (matching the nominal pipe thread size). Black graphics beneath show the relative sizes of 1/8", 1/4", 3/8", 1/2", 3/4", and 1" NPT fittings. A reader can use this chart to identify AN fitting sizes, match AN sizes to hose sizes and SAE threads, and identify NPT thread pitch and diameter, useful for fuel, oil, coolant, and brake plumbing work on any vehicle.