| All Patents in class 408/221 | 
| Patents 1 - 
					9
					of 9 
       | 
| Number | Date | Patentee | Title | Type | 
| 269,153 | Dec. 12, 1882 | F. Armstrong | Thread Cutting Die | taps and dies | 
| 422,024 | Feb. 25, 1890 | A.B. Landis | Screw-cutting head | screw machines | 
| 480,175 | Aug. 02, 1892 | R.J. Dearborn | Screw Threading Die | taps and dies | 
| 574,721 | Jan. 05, 1897 | C. Elterich | Thread Cutting Implement | taps and dies | 
| 575,148 | Jan. 12, 1897 | J.L. Chapman | Chaser Die | thread chasers | 
| 816,570 | Apr. 03, 1906 | J.D. Edmonds | Tool For Straightening Bolts and Retracing the Threads Thereon | alligator wrenches | 
| 1,017,884 | Feb. 20, 1912 | A.B. Landis | Cutter-head | metal threading machines | 
| 1,395,252 | Nov. 01, 1921 | E.E. Beck | Thread Cutting Die | taps and dies | 
| 1,866,542 | Jul. 12, 1932 | E.T. Bysshe, R.R. Finn | Chaser | thread chasers |