Grade 435, 17 ruby and sapphire jewels adjusted to 3 positions, manufactured from 1918 to 1919 a total of 310 movements in 4 runs make up this grade. Model 1XT open faced; bridge movements of high quality with Illinois superior motor barrel, double roller and simple regulator.
Observations, The movements have brushed nickel pattern and all named Illinois Watch Co. They have burnished set jewels on the bridges and silver snap on bezel dials. This was the first of the Extra thin models to be made and came in solid gold cases and were factory cased, with the low production figures it's rare to find this model complete with original cases.
Description, 17 ruby and sapphire jewels; adjusted to heat, cold and isochronism; has a specially quality tempered and hardened compensating balance; double roller escapement; steel escape wheel; gold center wheel; Breguet hairspring; simple regulator adjustment; and safety recoil click.