Rubber Duck

A rubber duck is a toy made of soft plastic that is shaped to look like a duck and also painted like one. Being hollow, it can swim on water and can squeak when squeezing it. It appears in Ultima VI.

Description
The sewer worker Daros had a never-ending supply of these and didn't hesitate to give the Avatar one each time they parted. How exactly such an item made of plastics -which requires industrial process to create- ended up in Britannia is a mystery that remains unsolved.

Trivia

 * This item is essentially the continuation of the long-standing duck-related jokes in the series.