A questioner said:

Anyone know what this is for? It came with my house from 1948. Measures about 4.5” x 5”. Front part lifts up. The only markings is a handwritten “50” on the back. Looks like it would have originally been black.

More info:
Can’t find any info on Google about it. Probably made in the 1940’s. Hanging in basement of my house in southeastern Michigan.

Some of the answers:

1. It looks like a device for dispensing something that rolls, like ping pong balls. But it looks very heavy duty for such a light item. Something along those lines maybe?
2. Could it be for holding mops horizontally, with the heads hanging over the sink to drip dry?
3. Would it have held folded up towels, perhaps cleaning cloths?
4. Anyone saying it’s for dispensing anything more or less spherical, like golf balls or eggs, is wrong. If you’ve ever seen a dispenser for those kinds of things, they need rails to roll the object back and forth so they don’t bind up on one another right as the entrance.Outside of that, I can’t comprehend a use. If it’s for dispensing things, you’d expect the top to open, not the front. If you want to be able to latch things in, then the front where the latch is needs to be the biggest hole, but the sides are bigger which means it’s just as easy or easier to pull things through the side. I could see it potentially being used for placing specifically shaped dispenser bottles sideways so that their cap sticks through the latch and 4 of them would be accessible, but that seems oddly specific.

   The last thought I have is that it could be something circular or that has one or more loops. Hoses or cords or cables could be hung on there and then the latch would keep them in place. When you need it, you open the latch and slide the whole looped bundle off at once. My biggest issue with that is that you’d need larger loops on higher hooks to keep any higher bundle from blocking any lower bundle.

   Winding a single cord or hose is really the only thing that makes sense. You start winding the hose on the lowest hook making 3 or 4 loops. Then you loop it higher and higher as you fill the slots with larger and larger loops.

   I still don’t like it as I would expect each layer to be bent slightly at the front, like the bottom layer is, in order to make it easier to slide the cord or cable on and off.

5. I didn’t see any mention of the handle on the top of the device. It looks like it is supposed to be removed from the wall and carried somewhere for use.
6. Silk stockings drier
7. If it’s near the well pump it might be a hose rack. Logical place to have one.
8. Man that first pic had me so confused about its size. I was thinking bowling balls first. From the comments some other people didn’t get too deep into it.
9. Could it be for holding and dispensing laundry bluing?
10. It reminds me of a salt lick holder for animals.
11. kind of reminds me of those skateboard racks you sometimes see.Open it up, slide it in with the wheels over the bar, close it and lock it
12. Tie rack or pantyhose drying rack?
13. Only thing I’ve ever seen like this was for holding multiple whiskey flasks. One in the coat pocket, four more filled for the rest of the work week (remember, this was the 40’s to 50’s) then the bar closes over the cap ends. It was a home made dealie but the open sides, size and bar are nearly identical.
14. The shade of paint reminded me of a hospital. Apparently there is a color called “hospital green.”
15. Not American so not sure but before the advent of modern replacements, did cloth washing soap come in balls? You know to put in a machine machine?