In my experience they have a bigger jar, and tiny lumps (like tiny meatballs or bits of pasta) in the same smooth puree as stage 2 ( and stage 1). By the time we got to that stage Fraser was on 'family meals' - mashed if need be, and we only used the jars occassionally. But then he would not eat a whole jar so I kept a third or half and just added to the next days home-made (frozen) meal. With Arwen I tried her first stage 2 jar today since I don't have a food processor here all her meals have been mashed with a fork or potato masher, and she loves lumps... but this was supposed to be vegetable pasta - but as smooth as a stage 1 jar.
