I bought the batteries in Morrisons for mine the other day and even managed to fit it myself. So it must be easy. Just use blunt flat end of a screwdriver to prise two parts open.

I don't know why you say "not Paddocks" but I wish I'd seen this b4 I used em. I phoned and asked for five wheel nuts. The guy asked the model took the card details. Next day wrong nut are deliverred 'from the manufacturer'. My car has roughly 18 mm studs these were roughly 14mm nuts...