This portable pump tank makes other models obsolete. While other canvas tanks are single walled and burst easily, this is the only double walled pump tank on the market. A tough and replaceable inner bladder gives extra strength, making the unit durable, cost effective and easy to repair. This is the only pump on the market with "Lubeport" a new design which allows you to lubricate the unit without having to take it apart. 5 gallon capacity.