lp identifying/translating Japanese Imperial Navel Tachymeter

[Aeroseer777]

My friend has a rare 12 second timer, made by Seikosha SKS serial number 13230 inside the case, other markings in the case indicate that it belonged to the Imperial Navy. It works. It has a 3 click stopwatch function, well that is it's only function I believe. I'm currently struggling to find someone to properly translate the kanji .If you could help me identify it what it timed that would be cool too I can't find another anywhere on the internet and nobody seems to know anything about it so I would be great fun for any help you might be able to provide. Thanks for your timehttps://www.dropbox.com/sh/wqvv2dkkf...hCClcIVPa?dl=0

[Aeroseer777]

Does anyone know what the 275 mark stands for?

[GHP]

Does anyone know what the 275 mark stands for?

横
Yoko [Yokohama?]

番２７５号
Ban 275-gō
No. 275
possibly a model number or issue/property control number?

--Guy

[Aeroseer777]

Correction to original post

This is a 15 second timer.

[Aeroseer777]

Correction

This is a 15 second timer