TheraBand Soft Weight, Hand Held Ball Shaped Isotonic Weight for Strength Training & Rehab Exercises, Pilates, Yoga, & Toning Workouts, Home Exercise Equipment Balls, 4.5" Diameter Hand-held and round More functional, accommodating grip for unilateral or bilateral exercise progressions Unique filling, which contains no latex, allows the ball size to remain constant at 4.5 inch