1,HOW TO FILL: Fill water (under faucet or with the tube provided - make sure the pin is down for this), then push the pin in the up position to open it for the air, attach the pump and start rocking it, the fuller it is, the heavier and more stable it becomes. Less water makes it lighter but more unstable.2,STRONG AND DURABLE: Are you ready for a hard full body workout? Weighing only 2 .8lb when empty. Fitness water bag are easy to transport and prepare for exercise. Fitness water bag with water are super tough fitness sandbags, filled with air and water. Valve makes it very easy to fill and empty the bag.3,MULTIPLE FUNCTIONS: Get this training for your core, legs, arms. Different handle positions allow for in your exercises. When full weighs up to 25 lbs 4,PORTABLE AND VERSATILE: Our fitness water bag are perfect for cardio, high intensity interval training for and all opympic movements such as lifts, swings, curls, step-ups and rows.5,TRAINING EQUIPMENT: Get the full body workout through instability. Pick up the and you immediately feel its unforgiving properties. The entire weight of the water sloshing from one side to the other in response to the smallest tilt. In order to raise it above your head, even the smallest muscles are activated, working together with the bigger muscles to maintain balance and power. Because of this, even 15 pounds of water can humble trained athletes.Colour:TransparentMaterial:PVCSize:75 x 20cmPackage Contents:1 x Fitness water bag1 x air pumpOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.