Loved these for packing for a three week trip to Europe.  The small is really small, the large really large.  The medium is just right for most packing needs.  Stronger than past compression packing bags I have used before, and they  hold their compression during the trip and have been doing well on other trips since.  Even if the yellow thing comes off, it just slides right back on for closing---easier to close than past versions.  Like how using bags like this increases room and makes it easier to stay organized while on a trip.  Stayed in one room in Italy that smelled musty and my clothes stayed smelling fresh!