This navigational computer is a celluloid disc form of slide rule computer specifically for aircraft navigation problems.
a) Front
Scale on rim labelled 'Disc A' scaled 10 –95 miles and 'True AS' (air speed).

Rotating inner scale dial 95mm diameter with several scales:
Ind AS (indicated air speed)
7 – 60 mins.
Also has apertures and scales for:
Altitude correction -50 - +50
Air temp Cent
Airspeed correction 0 – 30,000 pressure alt
Air temp 50 – 0 – 50 Cent.

A second, smaller inner disc has a Fahrenheit – Centigrade conversion scale.

b) Back
Rotating translucent dial, circumference inscribed 0 – 180 – 0 on rim, with two inscribed diameter lines at 90 degrees, a further radius line at 90 degrees, inscribed 0 – 70.
Behind, a fixed spiral graticule inscribed 80 – 280 (possibly mph or knots).

Inscriptions:
Printed on front: AMERICAN AIRLINES, INC. / NAVIGATIONAL COMPUTER / SOLD BY / GOBAL AIRCRAFT SPECIALTIES, INC. / FLUSHING, NEW YORK
Printed on back: PATENT NO. 2,026,537 DECEMBER 1933 BY H.M. JENSEN / REV JULY 1944
Serial no. C-15825-F

There is no instruction book but the instrument was presumably intended to compute ground speed and track from knowledge of corrected air speed and course. There is no case or box.

Dalton was the originator of several aircraft navigation computers, one type later referred to as the Dalton Computer