Kahler Human Clock Rack Unit- Rare And Vintage

Selling this Human Clock by Kahler. Very cool vintage rack module. 

I have no clue what this actually does, and do not have the means to properly test it. It does light up, and when connected to a midi port the on board light pulsates to the incoming signal, so I feel confident the unit works as it should. However, I am a selling it as is because of my ignorance on the subject. 

I will be including a manual I printed out from the internet on printer paper. 

Any questions, please ask.