Shaft Double C-ring model D, size 1 (S).Model D boasts dual rings for double the fun: it further amplifies sensation and ensures prolonged play. Made of 100% Flexiskin™ Liquid SiliconeSize 1 (S): Outside diameter 1.8 inch / 4,6 cmInside diameter 0.7 inch / 1,8 cm.Innovative Flexiskin™ feels just like skin: soft, squeezable,and flexible. This uniquely formulated liquid silicone is not only extremely soft and pleasing to the touch,but also hypo-allergenic and non-porous, so bacteria can’t become trapped in it. This makes the material highly realistic and completely safe for the body.