Nice and light, and seals well around the join, chosen for it's thermal resistance, and seems to be working well. Due to how light it is a little easier to destabilize it when standing without the cello inside but no concerns when the cello is in it. The orange color is great, very bright! One thing to note is that if you have a smaller frame the straps may not be super comfortable. As a medium sized person it fits me well and sits at a nice height on the back for use with public transport: not so high to worry about hitting tops of doors or lower ceilings, but high enough to not bump behind you even on steep stairs.