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Details and Image
Type | Model No. | Maker | Country | Construction Material | Date | Scale Length | Area of Use |
Disk | 510 | Boykin | U.S.A (Maryland) | Plastic | est 1960 to 1970 | Diam 13 cm | General Purpose |
Notes: "Spirial scale = 127 cm, 24 scales total both sides including a stadia scale, leather case, one image shows optional bar magnifier, one image shows parts, one image shows stamped markings prior to inking. Note 3rd and 4th images are of a 510 w/o magnifier."
Image 1
![](boykin/images/1790a.jpg)
Image 2
![](boykin/images/1790b.jpg)
Image 3
![](boykin/images/1790c.jpg)
Image 4
![](boykin/images/1790d.jpg)
Image 5
![](boykin/images/1790e.jpg)
Image 6
![](boykin/images/1790f.jpg)
Image 7
![](boykin/images/1790g.jpg)