| 1931 HANDLAN BUCK MFG COMPANY Lamp Patent Print |
| 1931 GREIST MFG CO Thread Cutter Patent Print |
| 1931 INLAND MFG CO Steering Wheel Patent Print |
| 1931 PULLMAN CAR AND MFG CORP Car Window Patent |
| 1931 SINGER MFG CO Hemmer Patent Print Art |
| 1931 PULLMAN CAR & MFG CORP Railway Car Patent |
| 1931 SAILER RUDOLPH Hemmer SINGER MFG CO Patent |
| 1931 DONALDSON MFG COMPANY LTD Golf Club Patent |
| 1931 COLT S MFG CO Firearms Magazine Patent |
| 1931 BUDDY L MFG CO Vehicle Toy Patent Print Art |
| 1931 SEYMOUR MFG COMPANY INC Coaster Sled Patent |
| 1931 LEEDY MFG COMPANY Musical Element Patent |
| 1931 GREIST MFG CO Ratchet Wheel Patent Print |
| 1931 ALEMITE DIE CASTING & MFG CO Truck Patent |
| 1931 SINGER MFG CO Embroidering Machine Patent |
| 1931 NESTOR JOHNSON MFG COMPANY Ice Skate Patent |
| 1931 OLSON BROS SAW MFG CO INC Clamp Patent |
| 1931 INLAND MFG CO Locking Handwheels Patent |
| 1931 SINGER MFG CO Sewing Machine Patent Print |
| 1931 FAUTLESS MFG COMPANY Undergarment Patent |
| 1931 MECHANICAL MFG COMPANY Bumping Post Patent |
| 1931 FORSTER MFG COMPANY Gas Cannon Patent Print |
| 1931 RAWLINGS MFG COMPANY Athletic Guard Patent |
| 1931 HUBLEY MFG CO Toy Patent Print Art |
| 1931 KING MFG COMPANY Popgun Patent Print Art |
| 1931 WILLIAM E PRATT MFG CO Air Gun Shell Patent |
| 1931 LEEDY MFG COMPANY Snare Drum Patent Print |
| 1931 GREIST MFG CO Sewing Machine Ruffler Patent |
| 1931 YALE & TOWNE MFG CO Truck Patent Print Art |
| 1931 PERFECTION MFG COMPANY Baby Carriage Patent |
| 1931 JEFFERY MFG COMPANY Gear Guard Patent Print |
| 1931 RAWLINGS MFG COMPANY Baseball Glove Patent |
| 1931 WILDER MFG COMPANY Toy Airplane Patent |
| 1931 LEEDY MFG COMPANY Drum Pedal Patent Print |