The following is a list of railroads and some of the airhorns they used. This is by no means a complete list and is intended only as a guide.

Amtrak
Nathan K5LA, Leslie A200, Leslie S3L

Atlantic Coast Line
Nathan M3, Nathan M5, Wabco E2

Baltimore and Ohio
Nathan M5, Leslie A200, Leslie S3L, Leslie S5T

Bangor and Aroostook
Nathan M3, Leslie A200, Leslie A125

Boston and Maine
Nathan M3, Leslie A200, Leslie A125, Leslie S3L

Burlington Northern
Nathan M3, Nathan P3, Leslie A200, Leslie S2M, Leslie S3L, Leslie S5T, Leslie RS5T

Burlington Northern Santa Fe
Holden M3H, Nathan P3, Leslie A200, Leslie S2M, Leslie S3L

Canadian National
Holden M3H, Holden K3L

Canadian Pacific
Holden M3H, Holden K3L

Central of Georgia
Nathan M3, Nathan M5, Leslie A200, Leslie A125

Chesapeake and Ohio
Nathan M3, Nathan M5, Nathan K5LA, Leslie A200, Leslie S3L

Chicago, Burlington and Quincy
Leslie A200, Leslie A125, Leslie S2M

Chicago and North Western
Nathan M3, Nathan P3, Nathan P5, Nathan K5H, Leslie A200, Leslie A125, Leslie S3L, Leslie S5T

Conrail
Nathan P3, Nathan K5LA, Leslie A200, Leslie S3L

Cotton Belt
Nathan M3, Nathan P3

CSX
Nathan P3, Nathan K5H, Nathan K5LA, Leslie S3L, Leslie RS5T

Delaware and Hudson
Nathan M3, Wabco E2, Leslie S3L

Erie Lackawanna
Nathan M3, Leslie A200, Leslie S3L

Frisco
Nathan M5, Leslie A200, Leslie A125, Leslie S3L, Leslie S5T, Wabco E2

Grand Trunk Western
Holden M3H, Leslie A200, Leslie A125

Great Northern
Leslie A200, Leslie A125

Illinois Central
Nathan M3, Nathan M5, Nathan P3, Nathan P5, Nathan K5LA, Leslie A200, Leslie A125, Leslie RS5T, Wabco E2

Kansas City Southern
Nathan M3, Nathan M5, Nathan P5, Nathan K5LA, Leslie A200, Leslie A125, Wabco E2, Leslie RS5T

Lehigh Valley
Nathan M3, Leslie A200

Long Island
Nathan M3

Maine Central
Nathan M3, Nathan K5LA, Leslie A200

Milwaukee Road
Leslie A200, Leslie A125, Leslie S2M, Leslie S3L

Missouri Pacific
Leslie A200, Leslie A125, Leslie S3L, Wabco E2

New Haven
Wabco E2

New York Central
Leslie A200, Leslie S2M, Leslie S3L, Wabco E2

Nickel Plate
Nathan M5, Leslie A200, Leslie S3L

Norfolk and Western
Nathan M3, Nathan M5, Nathan P5, Leslie A200, Leslie S5T

Norfolk Southern Railway
Nathan M5, Nathan P3, Nathan P5, Nathan K5H, Nathan K5LA, Leslie RS5T

Northern Pacific
Nathan P3, Leslie A200

Pennsylvania
Nathan M3, Leslie A200, Leslie S3L

Reading
Nathan M3, Nathan M5

Rio Grande
Nathan M3, Nathan P3, Leslie A200, Nathan K5LA, Leslie S3L, Wabco E2

Rock Island
Nathan P3, Nathan P5, Leslie A200, Leslie A125

Santa Fe
Nathan M5, Nathan P3, Leslie A200, Leslie A125, Leslie S2M, Leslie S3L, Wabco E2

Seaboard System
Nathan M5, Nathan K5LA

Soo Line
Nathan P3, Leslie A200, Leslie S3L, Wabco E2

Southern
Nathan M3, Nathan M5, Nathan P3, Wabco E2

Southern Pacific
Nathan M3, Nathan M5, Nathan P3, Nathan P5, Nathan K5H, Leslie A200, Leslie S3L, Wabco E2

Spokane, Portland and Seattle
Nathan M3, Nathan P3

Susquehanna
Nathan K5H, Leslie S3L

Tennessee Central
Nathan M5

Union Pacific
Leslie A200, Leslie A125, Leslie S3L, Wabco E2

Virginian
Nathan M3

Wabash
Leslie A200, Leslie A125, Wabco E2

Western Maryland
Nathan M5, Leslie A200, Leslie S5T

Western Pacific
Nathan M5, Leslie A200

Wisconsin Central
Nathan P3, Leslie S3L