Ding Feng 5751 Hyperbolic

Country of manufacture: China,            Date of manufacture: ____,      Date or Prod. Code: 5/18 (on edge of rule beneath LL1 scale)
Overall length: 32.2 cm,          Width: 5.3 cm,           Weight: 127.0 gms
Materials: celuloid laminate over bamboo, metal end plates
Cursor: 3.4 X 6.5 X 1.0 cms; plastic runners holding plastic lens, adjustable; lines = single hairline on both front and back
Scales: 26, no extensions
Front: LL1I, LL2I, LL3I, DF [ CF, CIF, H, CI, C ] D, LL3, LL2, LL1
Back: 2D, L, K, A [ Sin, H', Tan. CI, C ] D, Th, Sh2, Sh1
Gauge Marks: [1° (1745), e, R (5730) ]
Condition: C5 (Normal signs of use)
Came with: Origial black cardboard case