The 15 kg TRNR Hydro Bag is designed for ultimate instability training. It will challenge both your trunk muscles and postural control for improved core strength, spinal mobility, joint stability, coordination, balance,...

The 25 kg TRNR Hydro Bag is designed for ultimate instability training. It will challenge both your trunk muscles and postural control for improved core strength, spinal mobility, joint stability, coordination, balance,...