63mm diameter for single massage ball. Offering medium (50-55degree hardness) to firm (60-65 degree hardness) pressure.

Benefit
Perfect for rolling out large muscle groups such as back, hips, glutes and legs.
Relieve tight uncomfortable muscles and helping to improve circulation.
Enhance joint movement, enhance muscle recovery from workouts or the
floor to find the perfect pressure for your needs.
SGS-ASTM, SGS-EN71, SGS-SVHC tested certificate.