Outer diameter 3-9/16 inch (8.9cm); Inner diameter 2-7/8 INCH; Thickness 5/32 inch(4mm). Material: Food Grade Silicone. Soft silicone constructed better sealing,safe and not deformed,will not crack, or leak Suitable For Bialetti (only) Cafe Moka Express Dama 12 Cups. Not fit for: Venus, Musa, Kitty 12 Cups.Please remove the original gasket and measure the size before purchasing. If the size difference is within 0-3mm, then fit Silicone can be used across a wide temperature range from -65 degrees F (-54 degrees C) to 450 degrees F (230 degrees C) Tip: Silicone is more better seal softer and safe than original rubber ones Size: Outer diameter 3-9/16 inch (8.9cm); Inner diameter 2-7/8 INCH; Thickness 5/32 inch(4mm). Package include: 8 PCS silicone gaskets for 12 cups