ADOVA Fitness Aqua Bag, Adjustable Water Weight Bag with Upgraded Air Pump 45LBS Portable Aqua Training Bag Instead of Sand Bag Training Fitness Equipment for Workout Weights Training Balance : Sports & Outdoors

What an amazingly versatile piece of equipment. No heavy weights and the resistance is moving. This forces your body to use stabilizer muscles you do not get to use with regular free weights. The best thing is you can use this in the house without damaging your floors.