It's that heavy apron. We were out tonight. Beautiful evening, in the 80s. Decided to have a curry and take it is the park. "Let's sit on the grass." In a UK the apron always does its job. No matter how you sit or lie, the UK folds itself just right. You don't have to think about it. And no worries about the grass. Have to say I would not have been as relaxed in my wool kilts. Viva los UKs.