Mysterious Horseman attachment points

[loccdor]

These attachment points seem to be present only on Horseman 970 and 980 cameras as far as I've been able to tell.

They appear to be proprietary rails.

I can't find any accessory listed anywhere that fits them. Does anyone know about them?

 

[Willyekerslike]

They are for a customs cable release.

 

[loccdor]

They are for a customs cable release.

Thanks!

 

[ic-racer]

Yes, the cable release is designed for thumb actuation.

I jerked the camera too much with my thumb so I use the electronic solenoid release.