Hand selected - tried and tested by Anaya. 1 x Soft Stability Ball (25cm - PVC) This is a super versatile piece of equipment. Great for assisting you in curl ups/sit-ups by placing the ball under your upper back. You can use it to make your core stability work even more challenging by resting your pelvis on it and adding leg movements. You can use it to make your core stability work even more challenging by resting your pelvis on it and adding leg movements (remember if you do this watch out for gripping in your lower back. You might need to adjust how low your leg goes). The ball can also be placed between your legs to work your inner thighs. Please note that the ball shouldn't be fully inflated. It needs to have a sag in it to allow air displacement if you are resting your weight on it. It is not suitable to stand on for instance and have your full body weight on it but will hold your weight if your pelvis is rested on it or your upper back.