I think the extra weight is the aluminium RFID blocking mechanism. Bought one and got it shipped from the US to the UK about a month ago. A bit expensive at £80 but it’s sturdy, big enough for my 3 cards and about 6-8 notes folded. The magnet is really strong and worked out they lost magnetism around 800 grams. So about x4 iPhone 15 pro with a case. Pretty good. It’s not waterproof but certainly splash proof. Personally it’s a great product and I’d definitely recommend it.