Yeah, I don't do metric by default, so I sometimes mixup the exact conversions, especially from memory. It was certainly cL, not dL. It was a bottle of this, which is not special, but a novelty souvenir my wife wanted to bring home: https://stagsbreath.co.uk/products/stags-breath-liqueur-10cl

She ended up just having a 70 cL bottle shipped to us and we wrote off the one stolen at Heathrow.