These are handmade by a German woman that lives in Bavaria. These slippers do not have a tag. They are 100% wool, knit and filzed by her. The bottoms have an anti-slip rubber design on the bottom to help prevent slipping.
The maker recommends buying the exact size of the foot as they will stretch the first few times on. They are measured in cm by me to +/- 0.5cm. Measure foot from heal to end of big toe.