Najae Ab Wheel Roller with Knee Mat for Men Women Abdominal Core Workout Fitness Back Arms Exercise Double wheels and central divider design, which provide you better balance and more security Easy to setup and breakdown, no tools needed, this AB wheel is also lightweight and great to travel with Comfortable foam grips, the outer ring of wheel is made of polyurethane, which is mute and floor-friendly This ab roller is suitable for both beginners and advanced exercisers to develop balanced abs, arms, back muscles, core and upper body Knee pad is included (13.4Lx6.9Wx0.4H), wheel diameter: 5.7 (14.5 cm)