To me they seem to be a simpler, less expensive version of the trendy wool ones that are flooding the market. I particularly like the quality for the price. Birkenstock are my favourite style of sandal because they are so supportive to walk in. I ordered medium and I am a size12. This one is working as the original and thats exactly what I wanted/needed to keep using my headset. 5 (can wear 8. Highly recommended as does exactly what you would expect and good value. They definetly cancel out sound on like medium to medium-high volume with nice base. Due to the fabric they’re made out of, over time they start to stretch so I found myself adjusting the laces to tie them every morning and eventually I could even have to re-tie my shoes in the middle of my shift because I could feel them getting lose, keep in mind this was after maybe 8-12 months after wearing them 5 days per weeks so I’d say that’s the life time of a work shoe. Amazon has several of basically the same shoe for around 1/3rd the price.