Please insert into the pad pockets of bras or camisoles with cups. This is a set of bra pads with silk on the skin-contacting surface and organic cotton on the back. From the skin-contacting surface: 1. Silk 2. Cotton 3. Non-woven fabric 4. Cotton It has a 4-layer structure. ∴ The thickness is approximately 3mm. The skin-contacting surface is 100% silk, so it has a comfortable, soft feel and is recommended for those with sensitive skin. These are handmade bra pads created for those with sensitive skin, so you can use them with peace of mind. Diameter: 11cm Surface: 100% silk Back: 100% organic cotton