What Did I Buy? Kaywoodie Ceramic Filters

I went into a Seattle smoke shop to pick up a meerschaum I've had my eye on for years. Sadly missing its case, but with a signature of a mastercarver I haven't seen before. Seems the shop takes pipes out of their cases and puts those in a box in the back room; none of the cases they have back there fit any of the pipes they have now! While digging in the box of cases, I found this item.
Plastic tube with blue painted label having black text, reading "(clover-in-a-circle) Disposable ceramic filters for Kaywoodie filter-pipe" and "3 filters per pack 25¢" Inside are the three oddly-shaped filters, below some tightly-rolled blue paper which I imagine is instructions. The pastel blue plastic cap has another Kaywoodie clover embossed. I thought it was neat, don't know how old it is (the store supposedly opened in 1993) and they charged me a dollar for it.
Is this useful to someone? Is it older than the 1990s? Should I just put it on my pipe shelf as a curiosity? I'm not a Kaywoodie collector, but I do like their pipes.
Edit: I just realized the upper flat surface of each ceramic filter, where the air holes are located, has a clover deeply embossed. Nifty.
Edited by jvnshr: Title capitalization.

That's it! How old are those? The shop has a box of what I think may be bowls for that pipe. No idea if they have the rest, but I'll ask next time I'm down there. I'm going to go in each time I'm in the area, hoping to catch a different employee and see if anyone can locate the case for the meer I bought.
I think I'm going to also ask them if they'd like me to see if some of their mini meers fit cases they have. They could upsell them slightly that way.

I'll have to go back and see if the store has Filtronics. As said, I saw a box of wood bowls in their case and thought, what on earth do those fit!? The Filtronic bowls looks very similar. Is the Filtronic a pipe you're looking to find?

How does the bowl attach into the stem? What's the process for removal? I assume that, once installed, the filter is inserted and the metal cover is screwed in.

Thanks, that's a nifty design!