Denso gear reduction starter motor.
Find them on 1980s & 1990s Hondas.
Also on Chrysler engines.
Very Good starter.
Known to last 300-400 k miles on Hondas.
With it Chrome plated I would say it was for a Chrysler LA series 318-340-360.
Or a 383-400-440 RB.
Possible 426 Hemi.