Medium Fornax 4.0 -- Medium silicone -- F-3018 Grinder These are made of urethane

These are made of urethane resin

so it is just an aesthetic issue

Most of our molds are made with Dragon Skin 10 silicone

flexible flaps along the middle

This is a style of listing that features our Aelit and Deelit models in both sizes (slim and small) in our firm (10A) silicone

Medium Fornax 4.0 -- Medium silicone -- F-3018 Grinder These are made of urethane**Before buying, please familiarize yourself with our Store Policies and Shipping Policies. For information on silicone firmnesses, please visit the Our Silicone page.** Medium Fornax 4. 0 Firmness: Medium (0050) Color: gold, shades of purple Approximate Measurements: Total length: 8 inches Useable length: 6. 5 inches Diameter of the head: 1. 5 inch Circumference of the head: 5 inches Widest shaft diameter: 2 inches Circumference of the shaft: 6. 5