Self-massage therapy massage ball provides targeted relief to tight and sore muscles, especially in hard to reach areas5-inch diameter targets tightness in hard to reach places such as shoulders, traps, and hips to relieve muscle pain and improve mobilityGRID pattern promotes increased blood and oxygen flow to muscles for quick muscle recoveryLightweight, portable, and durable EVA Foam massage ball is an ideal travel companion on the roadIncludes access to free online instructional video library on foam rolling exercises from the experts at TriggerPoint; approximately 5" x 5.7" x 6.4"; 325 lbs. weight limit; 1-year manufacturer's warranty