HAFF PS4A drafting set, c. 1950s. The lens attaches to the pricker and provides 4x magnification; the 133APK ruling pen is designed for inking lines from 0.8 mm down to an extra-fine
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Ruling pen | HiSoUR - Hi So You Are
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Haff-made wing compasses from 1950s-80s. First patented by Haff in 1953, the wing compass features a spring release ratchet device for quick approximate settings, and a micrometer for more precise settings. Haff