No, they are knock offs of Westalee rulers for home domestic machines. They are just 1/8" thick, but they work well with ruler foot on low shank or higher shank machines. They are selling them off of Amazon. They come from Japan I believe, and take a while to get here. I have the original 6 piece set, and was going to order the circular for making Baptist Fan design. I ordered mine off Amazon.
https://www.amazon.com/gp/product/B0...qh_dp_hza?th=1