| All Patents in class 33/428 |
Patents 1 -
13
of 13
      |
| Number | Date | Patentee | Title | Type |
| 82,917 | Oct. 13, 1868 | G.W. Brooks | Centering Square | center squares |
| 89,625 | May 04, 1869 | W.H. Brock | Improvement in adjustable centre-square | center marking gauges |
| 229,283 | Jun. 29, 1880 | L.S. Starrett | Try Square | center squares |
| 249,821 | Nov. 22, 1881 | S.H. Bellows | Combination Square | center squares |
| 477,959 | Jun. 28, 1892 | J.B. Price | Center & Key Seating Rule | center marking gauges |
| 535,223 | Mar. 05, 1895 | W.S. Rowell | Measuring and Drawing Instrument | center squares |
| 567,869 | Sep. 15, 1896 | G.W. Snyder | Combined Rule & Try Square | try squares |
| 686,891 | Nov. 19, 1901 | W.A. Dunbar | Center Square | center marking gauges |
| 694,774 | Mar. 04, 1902 | K.O. Muehlberg | Center Square | center marking gauges |
| 738,422 | Sep. 08, 1903 | A. Duffy | Machinist's Try Square | try squares |
| 769,992 | Sep. 13, 1904 | G.M. Engel | Combined Center or Other Square | special purpose gauges |
| 1,429,793 | Sep. 19, 1922 | E.T. Strauss | Center-Finding Instrument | center squares |
| 2,085,461 | Jun. 29, 1937 | J.S. Chafee | Combination Rule and Slidable Head | try squares |
