Japanese online retailer Village Vanguard catalogue of quirky goods, including soothing RPG save crystals and wearable tentacle plushies, appears to be constantly expanding.

This time they're letting their penchant for oddities take a backseat to practicality, however, as they are now offering a very convenient foldable eco bag that fits right in your wallet.

Developed by daily goods maker CB Japan, the "ieco" bag is the size of a 1,000 yen bill, meaning it can slide perfectly into a wallet and make quick runs to the store with just your wallet and phone that much easier. It's also a great help for those that tend to forget to bring their own bag when shopping.

The miniature eco bags are just 25g in weight, but can carry up to 5kg of goods and come in three colors.

The ieco bags are available in Japan from Village Vanguard's online store, as well as from Amazon.