the mattress came rolled up and once i opened the packaging, it inflated to about 9.5 inches within a minute or so. it did initially have a weird chemical smell, but that's faded. it's so comfortable. firm but not too firm. i bought this mattress because my old innerspring mattress was causing me to wake up each morning with back pain. after my first night on this mattress, i woke up feeling great. also, today there was an earthquake in the nyc area as a result of a large quake in virginia. at the time, i was laying in my bed and i felt nothing! it really does absorb energy/movement. it is a great value for a great price!