Thank you for viewing. Please feel free to comment if you have any questions. The OMM Ultra Flexi Flask is a very practical and easy-to-use water bottle with a capacity of 500ml. The flask is designed with a compression body that shrinks in size as you drink. This prevents the empty space that can fill up inside the flask, which can cause the drink to slosh around, making it quicker and easier to drink from the bottle. The bottle has an easy-to-use bite valve, allowing you to drink easily from the bottle while on the move.