Stand strong for crystal clear waters with the Dopper Steel 350 ml. This knight in shining armour is cool and robust and fits perfectly into a sports bag. A must-have for those of you who love sports and the outdoors! This insulated bottle will keep your water, tea or coffee hot for 9 hours or cold for 24. The Dopper Steel holds 350 ml.. The three-part design means its easy to fill and easy to clean - by hand or in the dishwasher (max 65 degrees).