I just was looking at a thread about how to go shopping with baby. Thought I would pass on a bit of random knowledge. I discovered that the capsule would actually clip on to the trolley. If you open the seat meant for older children your capsule fits neatly across the seat front to back and has two nifty little metal clips that clip right on to the trolley and securely hold your capsule in place. To remove ot again you just push in the metal clips with your fingers and lift the capsule up.