5 - the size 8 fits roomy but comfy. I originally used a cheap lapel mic, to test the setup and it worked perfectly, but was inconvenient. You wouldnt want to damage your hearing! They are very comfortable without socks I would recommend them to anyone that loves shoes without socks. While the slippers are unisex, I still see them listed under women?s sizes, men?s sizes and European sizes. AP mode was pretty easy to use using the Smart Life app and I had no troubles. I ordered two packages of ten sets. Oh well! Other than that, a very nice pair of flip flops! I thought it would make a good work bench but I think about all its good for is laptop.