Perfect Design For Comprehensive Massage-This split peanut-shaped massage ball is a perfect design to get to those hard to reach stabilizing muscles that surround your spine and vertebrae without applying pressure on them as you lay on it.This peanut massage ball is a ideal for fathers day giftsDurable Material- The massage ball is made of natural rubber, which is firmer than tennis ball, but not like the hard plastic balls with knobs and they hurt. It is durable for long-lasting use. 4 colors have the same density for choice.Free Carry Bag- This Double Massage Ball comes with a bag to carry, perfect for use at the gym, on the road, before or after workouts. You can easily press on your neck, back, legs, feet, shoulders etc. at any time.Workout Guide- The back massage balls is comfortable and easy to use according to the instructions. You can use on painful localized parts of the body where trigger release is required while strengthening your core to stabilize. Satisfaction - If, For Whatever Reason, You Don't Absolutely Love Your Massage Ball, Please Feel Free to and We Will Here to Help You Any Time. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.