Any advice on bellows adaptors

I recently bought from the auction site a set of Asahi Pentax bellows the price on the box is £10.2/3p to show how old they are ..

Thet are 42mm and I bought an adaptor for a K fit which looks fine.

Now here is my problem the 42mm thread is both ends of these nice bellows and the adaptor which has arrived I thought would screw on the end and then I pop a K fit lens on but the adaptor seems too small unless I was to fit it to my lens is this correct ?
The other issue is should I have bought two as the 42mm thread is both ends

Any advice would be appreciated
TIA

oops just took a look and see these are for spotmatic so it looks like an in the cabinet job !

You can use them if you get a screw mount lens.

I have used this setup for things that don't move at all. For things that could get spooked it's best to use a bellows with auto aperture control.

I doubt there is such a thing as a K lens to screw mount body adaptor because the throat of the screw mount lens is smaller than a K mount.

The adaptor you have will let you fit the bellows to your camera body, but be careful, the bump that holds the pop up flash can foul the bellows making it very hard to get them off on some Pentax bodies. I got around the problem by interposing an extension tube between the body and the bellows.

That said you will be happier if you get a set of K mount auto bellows.

50mm F1.8 SMC Takumars are common enough on eBay, the ideal lens is the Bellows Takumar which doesn't have a focus ring.