only gave 2 stars because my order was 5 days late and that was very disappointing and I?ve read other reviews from this seller about the same issue so I?m not the only one. Now the sound quality, which is superb; tried them with my phone and tablet easy, quick pairing, and crystal clear sound. Measure the door thickness. I fist order a small,then I read a comment,it suggested that I order a medium,I weigh 128 lbs. The electric motor is fast and lift the phone handle quick and the system electronic overall works as promised. Pictures or videos really dont do this keyboard justice. Well done designing and manufacturing this. sizes -- which is someone guessing at the size relative to the Birkenstock size which are ALWAYS whole sizes European unisex. I paired them to my Pixelbook ro listen to Spotify while I browse the Internet. Currently have it on my ps4 for the past 4-5 weeks.