These ink cups are made from food-grade silicone,non-toxic, & odor free. These ink cups are also autoclavable at 175 ℃ -280 ℃ for sterilization. The special design suction cup base design will stick to any smooth surface. You will also no longer damage you need if you dip too deep. These ink cups are #12 Ink Cups. This is larger then your small #9 but not as big as your #16 ink cups. So its more in th emiddle range which most people are looking for. 22mm (Diameter) x 12mm (Height) x 2mm (Thickness) (diameter*height* thickness). Sold in 100pcs/jar and are available in 4 colors: Blue, Green, Pink & Mix.