"Neoprene sheet with adhesive" You can find it in amazon www.amazon.com/dp/B08R9LF7BX/ref=twister_B09W1Z2K89?_encoding=UTF8&th=1&fbclid=IwAR0VUU3Qz6xyXyxxdfEnc8e3He8U-hpXEpNS-bqpF96HqqEXMdIOTmGNoKU
Because the other side have gussets. So the coin slot can open widely. You can refer pattern anatomy in the Sewing Instructions to get clear view on the coin slot gussets area.
I bought this pattern but it has no written instructions. The tutorial should accompany the written instructions. I really like this wallet but I don't want to be forced to watch videos with music I have no desire to hear and no verbal tutelage. I hope that in the near future, someone will put out a tutorial in English that offers a better learning experience.
At the moment we can only provide video tutorial 😊. It is stated in the description 2 times that sewing step is entirely in video tutorial. We also add on another sentences "Please READ the description carefully and WATCH the video tutorial on our RU-vid channel BEFORE purchasing the pattern. Video speed (faster or slower) can be adjusted in the playback setting. Make sure what we deliver will suit your preferences"