FUN FACTORY has been become one of the most requested product lines this year. This German company is known for making premium body safe material toys that appeal to any company interested in carrying superior-quality toys. The sporty and Euro design and vibrant colors make this high-quality line of toys appealing to modern consumers. This European version of Ben Wa balls stimulate, massage and train vaginal muscles. The smaller weighted balls inside create a gentle to intensive vibration resulting in an intimate massage. Smartballs are made of hygenically body-safe "elastomed". They are very durable and easy to clean. The unique design, velvety smooth surface and numerous color variations are pleasing to the eye. Fun Factory's patented manufacturing method make Smartballs the most quiet love balls in the world. Smartballs are designed to enhance sex play because they train vaginal as well as pelvic floor muscles. Recommended by midwives. Detailed operating instructions are included and a sample of Bodyfluid lubricant in every package of SMARTBALLS. Measures 4" end to end with 3.5" string Safe for use with any lubricant Can be peg-hooked or shelved