A small lizard of Britain and Ireland which grows up ten inches long. The moke has never been noticed by Muggles thanks to its ability to shrink at will. This habit of shrinking when approached makes the lizard’s silver-green skin prized by wizards and witches for purses and money bags, which will contract on the outside while leaving the inside space unchanged when strangers come near (FB).
Hagrid gives Harry a mokeskin bag for his seventeenth birthday. Rufus Scrimgeour brings Dumbledore's bequeathed items to the Burrow in his (Scrimgeour's) own mokeskin bag (DH7)
Neither Hermione's beaded bag nor wizarding tents are ever described as being made of mokeskin, but both have properties similar to those of mokeskin bags.