I totally forgot about that product. That was pre-Apple when they were searching for a product. That an illegal device for stealing phone calls from the phone company. Probably wouldn’t have had as much world-wide demand as Apple has today.
My wife and I have several rotary phones around the house, although not as vintage as yours. Yeah, kids can’t believe we used those things to make calls. Most people don’t have land lines anymore, we decided to keep ours because if cellular services go down the land line continues to work, even without power. I like collecting and keeping antique gadgets. Steve Jobs motto was to look forward, never backward so Apple never kept old stuff. Probably why they’re successful. (I am, but wife is after me to dump the old stuff, sigh.)